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Topic cluster / Regime detection and contextTurning a strategy fully off makes sense when the regime invalidates the edge or the execution conditions behind it. Sizing down is better when the edge still exists but becomes weaker, noisier, or less deserving of scarce capital.
What to remember
Use a hard off switch when the hostile regime breaks the actual premise of the strategy, not just its comfort level. Use a size-down rule when the strategy still has some edge but the expected payoff, liquidity, or confidence has clearly deteriorated.
The wrong mistake is pretending those are the same decision. Turning something fully off is a structural claim. Sizing down is a confidence and risk-budget claim.
A binary gate is usually cleaner when the strategy becomes actively dangerous in the bad regime. That can happen when execution quality disappears, the sign of the edge flips, or the tail risk becomes much larger than the historical average suggests.
Sizing down fits better when the edge weakens by degree instead of disappearing entirely. In that case the context layer is not saying do not trade. It is saying this is not the moment to express the same conviction with full size.
Run the same base strategy under both policies and compare net return, drawdown containment, turnover, and sensitivity to threshold changes. Then ask the practical question too: which rule would a human operator still trust when the market becomes chaotic and the model starts disagreeing with itself?