He did dip versus Arizona but they have graded him at below average every other game before that too. Part of the reason for that I believe is because he has an uncanny knack for messing up at the wrong moment.
A lot of his infractions happen at very crucial moments and seemingly directly affect the scoreboard. For example, a holding penalty that takes them out of FG range or wipes out a big play that got them into the RZ. I don’t know PFF’s formula but I suspect they weight those types of infractions very heavily.
That’s my guess because to me, it looks like he performs well for the vast majority of the game and right when you don’t need something bad to happen, there’s a flag or other major error on GRob.
