This appears to be a built-in way to achieve that (v1.7.4):
git for-each-ref --sort=committerdate refs/heads/ --format="%(committerdate:short) %(refname:short)"
This appears to be a built-in way to achieve that (v1.7.4):
git for-each-ref --sort=committerdate refs/heads/ --format="%(committerdate:short) %(refname:short)"