Frankly, I don't know the rule's technicalities except that you cannot line up over the Center.
However, once the ball is snapped, is it really that the Long Snapper essentially cannot be contacted? That would mean that the gaps on both sides of the Center are off limits. Being a defenseless player doesn't mean he can't be contacted, it just means he can't be roughed up.
Anyone know if Arians is right about the rule?
And BTW: anyone notice that one of the sacks on Goff occurred by the Card's D player taking him down around the ankles in the pocket? In fact the player got up and kinda looked around to see if there was a flag. There should have been; you can't contact a QB in the pocket below the thigh.
So the idea that Arians says officials miss calls is like saying the sun goes down at night. This isn't news.