To think about it. I agree.
But, what if he has watched ungodly amounts of game film and is potentially 90-100% healthy by kickoff.
I still agree, but it is the NFL and players are rushed back.
If it was a knee scope to fix tissue, this website points out it will take up to 6-8 weeks to recover. http://orthoinfo.aaos.org/topic.cfm?topic=a00299
Now, when it first broke Marrone explained that he wasn't worried and in was minor surgery.
Today, Marrone mentioned he has been conducting field workouts and processing game film.
Stole this from rumblings, "Manuel has not yet been cleared for practice - he hasn't thrown a ball in a week - but Marrone said he has been conducting field workouts and hitting the classroom hard. The plan, according to the head coach, is to assess Manuel's Week 1 preparedness on the first day he's back on the practice field, whenever that may be."
http://www.buffalorumblings.com/2013/8/27/4664350/ej-manuel-injury-update-bills-qb-doing-footwork-drills-more