Couldn't this just be in git commits and give the a skill to look there?

Not really. That's like saying a design document should be pulled out of commit messages. There are a few reasons I can think of why this would be a bad idea. Maybe the biggest is that commit messages should be quickly readable and only explain the changes in the commit. To truly explain the reasons a path was chosen by a LLM you need at least a summary of what was asked for, and related discussions or "don't do" instructions. I've heard of people wanting to commit the entire chat logs as files before, but that is noisy and might only get you halfway there as far as explanations go. I certainly don't want this data bloat, snooping, etc. I would rather for important details to be curated. I can see why maximum details could be helpful sometimes but I don't want to bloat the repo with that.