[wyoung2]

"Detached head" is Git's way of saying "I don't know how to find my children when you say something like 'git checkout abcd1234'". Fossil can do this, so you can point someone to a historical checkin and Fossil won't get lost should you later commit on top of it. Git's warning you that if you do that, you may end up with an orphaned commit.

[rezonant]

More like "I don't know what gitref to move (*well, change) if you commit". `git checkout` isn't relative to the current ref is it?