Gillislee sucks, but he is still on the team only because he was a Jeff Ireland special this year. At least Gray could have helped with short yardage. Gillislee is garbage.
Once he got comfortable in the preseason Gillislee actually showed nice burst and the ability to make something happen in the open field. I don't think he's starting RB material, but he will probably chip in a couple nice plays this year if given the chance.