git checkout throws an error on --assume-unchanged files
After some amount of use I now prefer git update-index --skip-worktree which is a much better alternative to the git update-index --assume-unchanged.
Check out Difference Between 'assume-unchanged' and 'skip-worktree' for further information.
I also am planning to check out the method specified in this answer to git assume unchanged vs skip worktree - ignoring a symbolic link, which seems to be more defensive approach.