git worktrees can also be useful if your build system needs different arguments per branch. For example if you keep multiple release branches installed side-by-side on your machine, it is easier to just run `./configure --prefix=/opt/release-X.Y` only once on a worktree instead of repeating this procedure every time you switch branches. That way you can even keep all your object files around and save the time to compile them again.
The same also applies to languages such as Python or Node.js, where you might have a different set of dependencies depending on the branch and don't want to regenerate your virtualenv or node_modules on every branch switch.
aaahh, so it can track un-tracked files too? that I can definitely see being useful - the lack of a "local" / "remote" git ignore split makes this kind of thing hard :|
(yea, there's .git/info/exclude, but you can't add it to a branch and have it only exist locally. and it has weird interactions when something becomes tracked later.)
The same also applies to languages such as Python or Node.js, where you might have a different set of dependencies depending on the branch and don't want to regenerate your virtualenv or node_modules on every branch switch.