All these "we have to keep Harvey for his blocking" responses crack me up. If it was that important to McVays offense then Harvey would be getting 1st team reps over the other TE. If he gets those reps in the next two games then he might have a spot, until then he's just as likely cut as anybody else.
I think it's more situational blocking that McVay is looking for. McVay likes to run two TE sets more for setting up passes. One can stay in to block while one goes out. He may use Harkey inline at times if they TEs can't get the job done. He really needs the blocking on 3rd and short. As reported Harkey was the best blitz pickup guy on 3rd downs. Harkey can help get Gurley going to early in the game. Just some thoughts.