Keeping a 'stuck log' during practice has beaten solving more problems

Whenever I'm stuck for more than 20 minutes, I write one line: what I was assuming, what I tried, what finally moved me.

After three weeks I read them back. The same two assumptions kept showing up ('the input is always sorted', 'I can use a hashmap here without checking the constraints'). Fixing those two did more than learning another twelve patterns would have. Anyone else keep something like this?