TBM 437: Tokens, Hours, Points, and Other Curious Proxies
John Cutler ยท email ยท 2026-08-17 Reader ๐ฅ๏ธ
AI Unit EconomicsSpeaking the Language of Capital AllocationDORA & Engineering MetricsMeasuring AI ImpactProxy Validity (Construct Validity of Measurement Proxies)Token Throughput
Tokens are the latest in a lineage of seductive measurement proxies -- hours, story points, flow metrics -- that organizations mistake for a theory of value because they happen to be unusually easy to measure, and the fix is not a better proxy but making the underlying causal model of value explicit (treating the team as the cost unit, funding durable lanes, stating falsifiable hypotheses) so that ROI becomes the *output* of that model rather than a number computed directly from an easy-to-meter input.
practical ยท mixed โ Argumentative in structure (a thesis defended through a sequence of case studies) but practical in aim: Cutler is arguing for a specific way of doing something -- fund teams and judge AI/engineering investment through an explicit causal model rather than through hours, story points, or tokens. The theoretical scaffolding (construct validity, manufacturing-vs-R&D economics) is in service of that prescription.
Structure
| Part | Role |
|---|---|
| Opening: the 'return on tokens' moment and the dumpling/buffet metaphor | context |
| Hours as a measurement proxy -- six construct-validity caveats (fungibility, quality-blindness, context-switching, non-linearity, long-term option value, non-independence of buckets) | evidence (case study 1) |
| Lean/flow metrics and story points -- their manufacturing lineage, the conditions (classes of service, stable demand, homogeneous units) under which they work, and why product/R&D work usually violates those conditions | evidence (case study 2) |
| The 'Alternative' -- treat the team as the cost unit, connect it to a causal model, fund durable lanes, maintain a business case, judge return through movement in validated proxies | conclusion / practical prescription |
| Tokens -- applying the same construct-validity critique to AI spend specifically, via a point-by-point comparison against human-capital investment | evidence (case study 3, the target case) |
| 'What theory of the system are we betting on' -- ten fill-in-the-blank falsifiable hypothesis templates, contrasted against a naive point-ROI sentence | conclusion / practical prescription, applied specifically to AI spend |
| Conclusion -- team funding as salaries + token spend, and the same 'what demand, what causal model, what durable investment' questions applied to that combined figure | conclusion |
Key terms
- return on tokens
The vendor- and executive-favored framing that treats AI token consumption as a clean, ROI-ready denominator -- used ironically by Cutler as the latest instance of a recurring measurement mistake, not as a framework he endorses. - theory of the system Proxy Validity (Construct Validity of Measurement Proxies)
A set of explicit, falsifiable causal hypotheses ('we believe X will reduce Y without materially increasing Z') that a team or organization commits to about how an investment produces value -- the thing a serious business case actually consists of. - classes of service
The manufacturing/Kanban practice of segmenting work by sufficiently different work processes or value profiles before comparing flow metrics across it -- without this segmentation, changes in throughput or cost may just reflect a changed mix of what was produced. - capacity (as distinguished from hours spent)
An emergent, designed property of a system (a factory, a team) representing sustainable ability to meet demand -- not a fungible resource that gets 'spent' unit by unit at the moment of use.
Propositions
- explicitThe current surge of interest in 'return on tokens' is driven at least as much by organizations wanting cover for layoffs they couldn't otherwise justify as by a genuine effort to understand how AI augments human capability.conf: high
- explicitcorroboratedHours, flow/lean metrics (including story points), and tokens recur as measurement proxies because they share three failure modes: overweighting the input ('I') side of ROI over the return side, favoring shorter-term easier-to-attribute use cases, and gravitating toward whatever is easiest to measure.conf: highrefines โMeasuring AI's Impact on Delivery Speed ยท p4 โ tbm-437 names three general failure modes shared by proxy metrics (hours, story points, tokens); part 2 itemizes four specific, concrete methodological confounds for one particular proxy (the actual:estimate ratio) and gives a design fix for each, which is more operational than tbm-437's general critique.supports โAre You Getting Your Money's Worth from AI? ยท p6 โ Shore's staff-cuts example is a concrete instance of the general proxy failure mode tbm-437 names: overweighting the input/speed side of ROI over the net return.
- explicitHours are not a fungible resource that can be infinitely reallocated -- skill-context specificity, time-of-day effects, and specialist bottlenecks mean who spends an hour matters as much as how many hours are spent.conf: high
- explicitThe relationship between time invested and outcomes produced is non-linear and threshold-based, so metrics that treat hours as a continuous, linearly scaling input misrepresent the underlying production function.conf: high
- explicitManufacturing-derived flow metrics (cycle time, throughput, WIP) require 'classes of service' segmentation to remain meaningful; without it, changes in throughput or cost may simply reflect a changed mix of work rather than a real performance change.conf: high
- explicitAny use of story points beyond a disposable tool to spark discussion, right-size, or reality-check a near-term commitment is a 'dereliction of duty.'conf: highextendsTBM 416: Investment Stewardship (As Habit) ยท p5 โ Generalizes Cutler's own earlier 'a bad proxy is worse than no proxy' point from story points specifically to the full lineage of proxies (hours, flow metrics, tokens) sharing the same failure mode.
- explicitIn R&D/discovery-style product work, 'waste' (failed experiments) is not inherently bad, because a failed attempt purchases knowledge for the next attempt -- the manufacturing framing of waste-as-pure-loss doesn't transfer.conf: high
- explicitcorroboratedFlow/lean metrics are genuinely valuable, but only for continuous improvement -- understanding bottlenecks and system health -- and should not be used as a proxy for investment or value itself.conf: highsupports โMeasuring AI's Unintended Consequences ยท p5 โ Both endorse flow/lean-style metrics for continuous improvement and internal trend-watching, explicitly not as a precise external ROI proxy โ the same discipline Cutler prescribes generally, applied by Shore specifically to value-add percentage.
- explicitcorroboratedThe workable alternative to precise-but-invalid proxies is to treat the team as the indivisible cost unit, connect it to an explicit causal model of value, fund durable lanes of focus, maintain a documented business case (causal assumptions, proxy validity, expected returns, uncertainties), and judge return through movement in validated proxies rather than by attributing outcomes to individual units of work.conf: highextends โJohn Cutler's Post ยท p11 โ Cutler's diagnosis that attribution-demands push teams to avoidance or fabricated causal stories extends the tbm-437 prescription to judge return via validated proxies and a causal model 'rather than attributing outcomes to individual units of work' โ same underlying critique of forced attribution, applied to team outcomes rather than AI spend.supports โTBM 437: AI and the Recontextualization Tax ยท p2 โ Both pieces (published in the same TBM 437 issue) share Cutler's broader concern with organizations substituting an easy/legible proxy (a flattened report, a token metric) for the harder work of maintaining an explicit, faithful model of underlying reality/value.
- explicitโก disputed & corroboratedTokens appear to solve the ROI-measurement problem because they are unusually precise and easy to meter, but this precision is illusory: it measures only the input side while the underlying value-creation system (augment vs. replace, commodity vs. differentiated capability, complementary assets) remains as uncertain as it was for hours or story points.conf: highcontradictsThe Agentic P&L: Beyond the Empire of Headcount ยท p14 โ Cutler argues token precision is a metering illusion masking a fuzzy underlying value system; this directly opposes the PNL piece's claim that cost-per-cognitive-outcome is meaningfully measurable and stable enough to serve as a managerial control metric.supportsMeasuring AI impact, assessing readiness, and new data trends ยท p6 โ Supplies the construct-validity mechanism explaining why DX's early warning -- that 'every token dollar is a good dollar' is starting to break down -- is correct.supports โCannotMeasureProductivity ยท p5 โ Fowler's point that even accurate function-point counts miss true value (30 of 100 FP actually useful) is an early instance of the general pattern the newsletter later names explicitly: an easy-to-meter input proxy (FP, tokens) is mistaken for a measure of the unmeasured value it's supposed to represent.supports โAre You Getting Your Money's Worth from AI? ยท p9 โ Both warn that token cost's apparent measurability/precision is illusory and unstable, and shouldn't be mistaken for a solid basis for ROI projection.supports โMeasuring AI's Unintended Consequences ยท p8 โ Both treat token-usage metrics as far noisier and less validly precise than their apparent measurability suggests, warning against using tokens as a standalone ROI or cost-of-change signal.
- explicitAI spending is not straightforwardly comparable to an equivalent amount of human-capital spending, because of structural disanalogies: employees generate positive externalities (knowledge, relationships, institutional memory) that token consumption does not automatically generate; salaried labor behaves as a fixed cost over the planning horizon while token consumption behaves as a variable cost; and the residual asset left behind by AI spend depends entirely on whether the organization deliberately captures it.conf: highrefinesThe Agentic P&L: Beyond the Empire of Headcount ยท p2 โ Complicates the PNL piece's clean 'cost per cognitive outcome replaces headcount' substitution by detailing structural disanalogies (externalities, fixed vs. variable cost, residual-capital capture) that make token spend and human-capital spend not directly interchangeable.
- explicitMarginal returns to AI spend likely decline as spend scales, because the first dollars target obvious, high-value use cases while later dollars chase increasingly marginal applications.conf: high
- explicitdevelopedA defensible AI business case is not a single point-ROI estimate ('$10M spent -> $30M value') but a set of explicit, falsifiable 'theory of the system' hypotheses, from which ROI is properly the observed output rather than the initial pitch.conf: highextendsTBM 416: Investment Stewardship (As Habit) ยท p6 โ Extends Cutler's Bayesian-updating framing for engineering ROI into a concrete template of falsifiable 'theory of the system' hypothesis statements specifically for AI spend.extends โJohn Cutler's Post ยท p2 โ Both treat a business/ROI claim as a falsifiable hypothesis to be tested and retired rather than a fixed pitch to be perfected; Cutler generalizes the same epistemology from AI-ROI business cases to team metrics in general.
- implicitTokens do not create a new measurement crisis so much as expose a pre-existing one -- many companies had already abandoned rigorous product-work ROI or value-architecture thinking well before AI spend became visible and metered.conf: medium
- implicitThe ease with which an input can be measured is inversely related to, not evidence for, how well-understood that input's actual economic return is -- an easy-to-meter cost can sit inside a value system that is unusually hard to pin down.conf: medium
Arguments
'Return on tokens' is not a solution to the ROI-measurement problem; it is the newest instance of an old, unsolved problem. strength: high
Explicit premises:
- Hours failed as an investment proxy due to fungibility, quality-blindness, context-switching cost, and non-linearity.
- Lean/flow metrics and story points failed as investment proxies because product work usually violates the manufacturing preconditions (classes of service, stable demand, homogeneous units) those metrics require.
- The same three failure patterns (I-side focus, easy short-term attribution, gravitation toward what's easiest to measure) recur across hours, flow metrics, and tokens.
Implicit premises:
- If a new metric shares the causal structure of prior failed metrics, it will fail in the same way regardless of how precisely it can be measured.
- Measurement precision of an input is orthogonal to the validity of using that input as an ROI denominator.
Inferences:
- Organizations and vendors currently embracing 'return on tokens' will eventually encounter the same attribution, non-linearity, and boundary-setting problems that undermined hours and story points, unless they change what they're measuring rather than just how precisely they measure it.
A serious AI investment case should be framed as an explicit, falsifiable 'theory of the system,' not as a point ROI estimate.
Explicit premises:
- Point ROI estimates ('$10M spent -> $30M value') hide unstated assumptions about augmentation vs. replacement, commodity vs. differentiated capability, complementary assets, and downstream/lifetime costs.
- Theory-of-the-system statements make those assumptions explicit and individually testable.
Implicit premises:
- An explicit, falsifiable hypothesis is epistemically superior to an implicit, unfalsifiable one even when both produce the same headline number.
- Organizations and teams are capable of tracking and updating belief in specific stated hypotheses over time, rather than only ever producing a single point estimate.
Inferences:
- Teams given responsibility for AI spend need a stated theory of the system, not just a budget, in order to make intelligent tradeoffs between people, models, tools, and other forms of capacity -- this is effectively a prerequisite for decentralizing AI-spend decisions down to team level.
Narratives
- The world shifted 'from a buffet model to buying each dumpling one at a time,' and now everyone is panicking about the ROI of each dumpling.
โ Supports the idea that the return-on-tokens anxiety was triggered by a change in the visibility/metering of AI cost, not by a change in the underlying difficulty of creating value with it -- the problem was always there, metering just made it legible. - The deep-onboarding specialist working in their 'magic hour' of uninterrupted morning productivity cannot be immediately swapped into a legacy backend refactor, and a highly skilled developer reactively pulled into unfamiliar code has less leverage than a more junior but contextually situated one.
โ Supports the proposition that hours are not fungible -- who spends the hour, and when, matters as much as how many hours are logged. - You might bang your head against a problem for eight hours and get nowhere, and the ninth hour unlocks all the value.
โ Supports the non-linear, threshold-based relationship between time invested and outcomes -- undermines any metric treating hours as a continuous input. - A team spends 5% longer on every enhancement to pay down debt and 'garden' the codebase; three years later, a version of that team (with some turnover) is 'absolutely flying,' but there's no clean place to 'book' that time or connect it to the eventual return.
โ Supports the case for treating the team as the cost unit connected to a causal model, rather than trying to decompose and attribute investment to individual time buckets -- some hours have compounding option value that no attribution scheme can capture. - Ten fill-in-the-blank 'We believe...' sentence templates, contrasted directly against the naive sentence 'We will spend $10M on AI and generate $30M of value.'
โ Functions as a worked example (rather than a narrative in the conventional sense) showing what a falsifiable, defensible AI business case actually looks like in practice, as opposed to a point estimate.
Questions addressed
- โ
Why does the return-on-tokens conversation feel so urgent right now?
A change in metering/visibility (buffet -> per-dumpling billing) surfaced a problem that was already latent, compounded by companies wanting cover for headcount reductions they couldn't otherwise justify. - โ
Are hours a legitimate way to understand investment?
Yes for understanding where effort is going, but only with explicit caveats about non-fungibility, quality-blindness, context-switching cost, non-linearity, long-term option effects, and non-independence of allocation buckets. - โ
Are lean/flow metrics (cycle time, throughput, story points) a legitimate proxy for investment or ROI?
No -- legitimate only for continuous improvement (bottleneck-finding, system health), never as a proxy for investment or value; story points explicitly rejected beyond disposable, near-term use. - โ
Is AI token spend comparable to an equivalent amount of human-capital spend?
Not straightforwardly -- multiple structural disanalogies (externalities, fixed vs. variable cost, residual-capital capture, marginal-vs-average returns, complementary assets) make direct comparison unsound. - โ
What should a defensible AI business case actually look like?
A stated theory of the system -- explicit, falsifiable causal hypotheses -- rather than a point ROI estimate, with ROI properly understood as the observed output of that hypothesis, not the input pitch. - โญ Is a working, validated measurement scheme for AI ROI actually achievable right now?
Cutler explicitly declines to claim this is solved: 'This is extremely important given that everyone is learning at the moment. No one has figured this out.' He reframes the question rather than answering it.
Gaps
- incompleteCutler never specifies who is supposed to build, own, and adjudicate disputes about the 'theory of the system' / causal model he proposes -- finance, engineering leadership, product, or some new function. Without a named owner and a process for contesting a causal narrative's validity, 'make your theory of the system explicit' risks becoming just as rhetorically gameable as the proxies it replaces: a leader can write a confident-sounding, well-formatted causal story without it being falsifiable in practice, and nothing in the piece specifies who would catch that.
Read next: Organizational-design and FinOps-style AI-cost-governance literature on who owns cross-functional investment decisions; DORA's Capabilities Model research on how measurement gets operationalized organizationally rather than just prescribed. - incompleteThe piece doesn't address Goodhart's Law risk in its own alternative. 'Movement in validated leading-indicator proxies' is still a metric, and once it's attached to a $1.5M-plus-token-spend team business case, it becomes exactly the kind of target Cutler spent the whole article warning is prone to gaming (as story points, deploy frequency, and PR volume already were). He treats 'validated proxies' as structurally immune to the same social/incentive dynamics he just diagnosed for every prior proxy.
Read next: extract-8-engineering-metrics-ai-broke's argument that Goodhart's Law has become inescapable under AI (metric-gaming as a side effect of normal tool use rather than something requiring extra effort); general Goodhart's Law literature.closed byAre You Getting Your Money's Worth from AI? โ Shore's 'measure the approach, then stop measuring' discipline โ never tying a metric to individual/team performance, and retiring it once you've learned from a given approach โ is a concrete, general mitigation for the Goodhart's-Law risk this gap flags in leading-indicator proxies, applicable regardless of which metric (tokens, PRs, or a validated leading indicator) is chosen. - incompleteNo discussion of scale or organizational-profile effects on the prescription. Does a $50M-token-spend enterprise need materially different governance from a five-person team's monthly token bill? 'Team as cost unit + explicit causal model' is presented as a universal recipe, but DORA's AI Capabilities Model research suggests AI-adoption outcomes cluster into distinct organizational-profile clusters -- implying that one governance recipe may not transfer cleanly across very different scales or team maturities.
Read next: DORA's 2025 AI Capabilities Model report on the seven data-derived team-profile clusters and their differing capability needs.
Closes gaps elsewhere
- The Agentic P&L: Beyond the Empire of Headcount ยท g4 โ Explains exactly why a 'cost per cognitive outcome' style metric cannot be as portable and stable as cost-per-FTE: precise per-unit measurement of the input doesn't resolve the fuzzy questions (augment vs. replace, complementary assets, marginal-vs-average returns, residual-capital capture) that determine whether outcomes are actually bounded, weighted, or comparable across functions.
- How to Respond to the Coming AI Cost Shock ยท g1 โ Directly answers 'how do you actually measure AI-driven ROI in the first place' by reframing the question: don't calculate a point ROI at all -- state explicit, falsifiable 'theory of the system' hypotheses and treat ROI as their observed output rather than the input to the calculation.
- SWLW #710: Revised rules of Eng Leadership, When AI costs more than the engineer, and more. ยท g2 โ Supplies the missing method for connecting AI spend to value that the SWLW piece skipped: fund the team as a durable cost unit tied to an explicit causal model, and judge return through movement in validated leading-indicator proxies rather than by trying to attribute revenue or user growth directly to AI spend.
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