Also, isn't it a major plot point that replicants are not allowed on Earth? So Deckard being a replicant operating on Earth is illegal; making his status as a

Also, isn't it a major plot point that replicants are not allowed on Earth? So Deckard being a replicant operating on Earth is illegal; making his status as a replicant "obvious", by endowing him with superhuman traits (or even self-knowledge) would be ill-advised!