In at least one of the various scripts (or treatments) I've seen, Gaff resents Deckard, believing that he should be given this particular replicant slaying job

In at least one of the various scripts (or treatments) I've seen, Gaff resents Deckard, believing that he should be given this particular replicant slaying job himself. Predisposed to dislike Deckard as he is, he criticises Deckard for not being able to understand and chooses not to make it easy for Deckard, and further insults him directly in Cityspeak.