Stevie Johnson facing Revis is a big issue, and I'd be more concerned about that than his groin problems. He will probably play, but I just don't see him being very effective.
I would not let Brandon Lloyd's preseason have any sway on your decision at all. Belichick is known for hiding talent and various schemes in the preseason.
Gronkowski had 1 catch for 7 yards in all of the 2011 preseason.
In 2007 Randy Moss had 1 catch for 9 yards for all of the preseason before going 1500 yds/23 tds in the regular season.
McDaniels and Belichick already know what they have in Lloyd. They aren't going to give any hints in the preseason. Start him.