That the bottleneck moved. For fifteen years the scarce skill was producing working code. This year my code output roughly tripled and my review and verification load more than tripled. The people around me who actually got faster did not have better prompting tricks, they had better taste in what to verify and the discipline to delete work that was plausible but wrong.

Smaller second lesson: writing things down got more valuable, not less. Specs, invariants, one page designs. The clearer the written thinking, the better everything downstream performs, humans included.

YMMV, but in my parts, most doctors or heath professionals, unless they themselves have faced being in a repetitive dehydrated state, or have a medical issue where they end up chronically dehydrated, will assume a normal blood pressure reflects good hydration state ... it does not. Low blood pressure could indicate dehydration, high blood pressure could be due to dehydration ... but it does not logically follow that a regular blood pressure means hydration levels are all good.

I'm the kind of guy who hands a manager a list of tasks, expects them to get done, and forgets about it. Well, that bit me in the ass hard this year. Daily checklists stopped coming in, and I didn't catch it for weeks.

My advice: put checks and balances in place to make sure things are actually getting done. I've now put a daily report in place for every store, and anything marked “No” needs an explanation of what they did to fix it. Also, make sure you have access to the accounts your managers handle before you need to take them over. Delegating something doesn't mean I can forget about it.