Too Long; Didn't Read
In this mode, commits in "detached" mode don't belong to any branch. Instead of creating a new branch, you can checkout the branch where you want to start the experiment. The changes you made while in this mode are orphaned and will be purge in the next garbage collection run. If I don't like the new color, I can just checkout other branch and forget about changes I made in detached HEAD mode. Now, if I like the changes, the changes are persisted in the new branch.