The problem this script solves is nicely described at "Multiple working folders with single GIT repository":http://finik.net/2010/10/24/multiple-working-folders-with-single-git-repository/
The solution is more or less a copy of that.
Add the bin directory to your path, or perhaps use basher:
basher install PeterHancock/git-groupTo create a git group
git group [email protected]:$user/$project.gitTo create a new working copy $dev
git group-add $dev