Following the tradition of sports, I propose that commit id e83c5163316f89bfbde7d9ab23ca2e25604af290 be officially retired.
I was under the impression that git hashes are generated based on the contents in a commit. If that's true you cannot retire them. They're not random.
In any case, I believe he was joking. The odds of a sha1 collision are very very low.