Probably was a Grade 3 tear -- that has a some serious recovery time.
I am surprised at the tweet that he wasn't impressing. Most of the commentators I read seemed to think that he looked very strong in the early phases of training.
Looks like Decker will be the next guy up. For sure, a better choice that Dez, both in terms of fit and price. Although I think Dez still has upside, with Hogan and Dorsett (and, at times Gronk), we have the middle / deeper ranges reasonably covered, and we traditionally are not a long ball offense in any event. With Matthews and Edelman out (for a portion), a good slot / slant / short pass guy is a great need, and I think Decker can fit that need better, in my view.