Seems like they’re not ready otherwise I’m sure someone else would’ve signed them as well. I think it’s safe to say that the Pats will be making more moves at the position before the season starts. Maybe even right after cutdowns, there’s always a lot of unexpected movement at that time.
One thing they cannot afford to do is hurry Gronk into the lineup, then throw him right into the fire playing every snap. Ideally you’d limit the amount of blocking he has to do. Maybe even just use him more as an “F” tight end, especially in the red zone. That’s where his biggest impact is.