Better yet, use a code review system, then automate a test that detects this and rejects outright any patch containing it. Sure, you can use this in your private repo, even keep it in your stashes/branches, but if it gets pushed to the central master, expect to be slapped down, hard.

cringe harsh, but fair. can't have this kind of idea spreading.

And since OP doesn't know how source control worms, he will never know how you found him.