Funny, I always heard this anecdote in the context of adding hair to Mickey Mouse's arms. Apocryphal indeed, I guess: https://www.npr.org/2014/11/17/364760847/whats-with-all-of-t...

In terms of function though, the "hairy arm" is the complete opposite though: it's not to make sure reviewers are paying attention, it's to distract meddling reviewers from the changes you don't want them to veto.