That doubt no longer exists. This morning, we learned from Gronkowski himself that he's been cleared to play:
Rob Gronkowski on Week 1: "I'm ready to go. I'll be playing."— Jeff Howe (@jeffphowe) September 1, 2014
Rob Gronkowski laughs when asked how it feels to break news he will play. Says he wanted to get it out of the way early.— Mike Reiss (@MikeReiss) September 1, 2014
The Patriots took the patient approach with Gronkowski's rehab this summer, much like they did in 2013. This means that we can be pretty confident Gronkowski is 100%, or as close to that number as he will get.
The Patriots offense looked much improved over 2013 this preseason without Rob Gronkowski. Getting Gronk back will make the offense that much more dangerous. For Gronkowski, he's out to prove he can play a full 16.