Trading Academy · Module 2 — Capital & risk management · Lesson 4/4
Every defense in trading has a price — hedges cost carry, stops cost whipsaws, sitting out costs the trades that worked. Cutting position size is the exception: it needs no forecast, no new skill, no product, and it is reversible tomorrow. The whole discipline is knowing, in advance, when it is mandatory.
The arithmetic case is one line long. Every number in lesson 2.1 scales with the risk fraction, so halving size halves the pace at which any losing stretch digs. The hypothetical 20% drawdown budget from lesson 1.1 that survives 22 consecutive losses at 1% risk survives 44 of them at 0.5%. Sizing down does not predict the streak or end it — it buys time to find out what the streak is, while the account stays off the vertical part of the recovery curve.
What it costs is proportionally smaller results for as long as the reduction is in force — a symmetric, temporary price for protection against the asymmetric, permanent thing. That trade is available at any moment, in any market, at zero fees. Almost nobody takes it, because the moments that demand it are exactly the moments a person wants size most: down money, sure the turn is near, owed a comeback.
Which is why the decision cannot be left to the moment. It has to exist as written if-then rules, drafted while calm:
| If… | Then… |
|---|---|
| drawdown from high-water crosses a preset line | halve the risk fraction |
| a preset run of consecutive losses arrives | halve it again |
| the system is new, changed, or in a market it wasn't built in | start at half size or less |
| the urge is to size up to win it back | smallest size, or stop for the day |
A shape, not a prescription — the full lesson is about filling in your own numbers before you need them.
The full lesson works through each trigger and the arithmetic behind it, shows why "revenge sizing" is the account-killer sequel to the first loss (with the doubling-down numbers), draws the line between sizing down and stopping entirely, and ends with an exercise: writing your own if-then table and putting it where you place orders.
Full lesson
The rest of this lesson — the worked examples, the exercises, and how our own system applies it — is included with any paid NoGuru subscription. Members receive a personal access link by Telegram DM; open it once and every lesson unlocks on this device.
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