> I'm surprised there are developers who seem to not get twice as much done with AI than they did without.

I think it depends a lot on what you work on. There are tasks that are super LLM friendly, and then there are things that have so many constraints that LLM can basically never get it right.

For example, atm we have some really complicated pieces of code that needs to be carefuly untangled and retangled to accomodate a change, and we have to be much more strategic about it to make sure we don't regress anything during the process.