All six problems are measurement failures wearing behavioural clothes.

The claim

Instrument the blind spot and the psychology problem shrinks.

The six problems are conventionally treated as character flaws requiring character solutions — more discipline, better mindset, stronger rules. The MARS position is narrower and more testable: each behaviour is a rational response to missing information, and supplying the information changes the behaviour without any appeal to willpower. That is a strong claim, and the useful thing about it is that it fails visibly. If a trader instruments a blind spot and the behaviour persists unchanged, the claim is wrong for that case. That falsifiability is the reason the claim is worth making at all: a theory of trading psychology that cannot be wrong is a theory that cannot be improved, and most of the popular ones are built that way.

Worked through

Each behaviour, and the reading that was missing.

The pattern holds item by item, and stating the missing measurement makes the behaviour look considerably less mysterious:

• Size creep after wins — no measurement separating edge from a favourable sequence.
• Revenge trading — no gate mapping a drawdown level to an authorised posture.
• P&L myopia — no expectancy figure, so the only available scoreboard is money.
• Variance panic — no benchmark saying whether this drawdown is normal.
• Unpriced friction — no per-trade accounting of spread, swap, and slippage.
• Silent decay — no drift detection, so decline is invisible until it is large.

Why the reframe helps

A measurement problem has a next step. A character problem does not.

The practical value of the reframe is entirely in what it makes actionable. Told that one lacks discipline, there is nothing specific to do on Monday morning; the prescription is an attitude, and attitudes are not tasks. Told that one has no per-trade friction accounting, the next step is concrete, finite, and finishable in an afternoon. The reframe does not make the problem easier — it makes it addressable, which is the difference between a diagnosis a trader can act on and one they can only feel bad about.

The honest limit

Some of it really is psychology, and instrumentation does not touch it.

The argument should not be pushed further than it goes. A trader who has the gate reading, understands it, and overrides it anyway is not suffering from a measurement gap — that is a genuine behavioural failure and no additional instrument will resolve it. What measurement does is strip away the large fraction of apparent psychology problems that were information problems in disguise, leaving a much smaller residue that is actually about the person. The residue is real. It is simply far smaller than the retail conversation assumes, and it is a different problem requiring different help.

Two groups, not six items

Three problems corrupt judgement; three corrupt measurement.

The list divides cleanly and the division carries information. The first three — confusing profit with edge, deploying risk emotionally, ignoring drawdown structure — corrupt what the trader decides. The second three — mismanaged open exposure, no branch attribution, no separation of variance from decay — corrupt what the trader can see. The second group is the more dangerous, because judgement corrupted by bad information cannot be improved by trying harder, and a trader working diligently on group one while group two remains unaddressed is optimising against a distorted picture. The grouping also predicts which traders are hardest to help: someone working diligently on group one while blind in group two experiences their own effort as ineffective, which is corrosive in a way the underlying problem is not.

Order of repair

Fix what you can see before fixing what you do.

It follows that the repair sequence is measurement first, and this is the opposite of how most traders approach it. Instrument friction, expectancy, exposure, and drift before working on sizing behaviour — not because behaviour matters less, but because behavioural work performed against a distorted picture optimises toward the wrong target and feels like failure even when it succeeds. Traders who reverse the order commonly report that discipline work 'did not stick', when what actually happened is that it was pointed somewhere the data never supported.