My friend and I were talking about this the other day.
Why not put Mario or Hughes over gronk* when hes not lined up wide, in the slot or the backfield? So if gronk* is anywhere on the line...just let one of those 2 guys engage him at the line with a safety or LB behind him to help. Both of those guys are physical enough to slow him at the line and beat him up a little.
I know this can make you susceptible against the run, but I'd probably take our chances if it meant eliminating gronk* from the game plan totally. Someone who knows X's and O's please let me know why this is a terrible idea.