◇ Could this help me?
Yes, with a pruning requirement attached. The habit is excellent and the reasoning is correct: the moment immediately after a mistake is when the precise failure is known, and capturing it then into a file that is read every session converts a one-off correction into a standing rule at almost no cost. It is also the rare technique that gets better the longer it runs. General practice, with the one thing the video omits: the habit is purely additive, so a file maintained this way grows steadily, and since instruction-following accuracy falls as instruction count rises, this needs a regular consolidation pass or it will eventually make everything else in the file less reliable. Adopt the habit and schedule the prune at the same time.
From now on, when I correct a mistake you made, do two things: fix it, and then write the rule that would have prevented it into my project instructions file. Show me the exact wording before adding it, and make the rule specific enough to catch the real failure but general enough to apply next time rather than only to this one case. Every time you add one, check whether it overlaps with or contradicts a rule already in the file, and propose a merge instead of a second entry. Separately, give me a short routine I can run monthly to consolidate the accumulated rules and remove the ones that no longer apply.