What does an overnight gap do to a plan you wrote calmly?

Why this matters. A plan is tested exactly once — at the moment it becomes expensive to follow. Everything before that is rehearsal.

You wrote the plan on a quiet afternoon. The market opens well beyond your level. The plan says one thing. Every part of you says the plan was written by someone who did not know this would happen.

The two failures, and they are opposite

Abandoning it because the situation is unprecedented — which it usually is not; it is simply the first time it has happened to you.

Following it mechanically into a situation it never contemplated, because following the plan feels like discipline regardless of whether the plan addresses the case.

The uncomfortable truth is that both can be wrong, and no amount of resolve distinguishes them at 9:31. The distinction has to be built into the plan beforehand.

What a plan owes you

The mechanics — gap policy, how a stop behaves when price opens through it, what a time stop does — belong to Technical Analysis, in Stop versus plan. What belongs here is the shape of the instruction: a plan that only covers the expected case is not a plan, it is a forecast with a stop attached.

The artefact

A written gap clause, and a second, smaller thing that matters more than it looks: a timestamped note taken before you act. Two sentences: what the plan says, and what you are about to do.

If those differ, you have not necessarily made a mistake — but you have created the only evidence that will let you find out later. Deviations that are never recorded cannot be reviewed, and unreviewed deviations become the plan.

Try it now

Read your most recent plan and find the case it does not cover. There is one. Write the clause it is missing, today, while nothing is open.