I've seen that happen. Heck, we had a punter back in the early 2000's that had a torn ligaments in his knee and continued punting throughout the season. He couldn't run, literally limped off the field, but he still could kick. It's weird how the same injury leads to different amounts of pain, mobility, etc.
You can walk around the world with a torn ACL. You just have to go straight. Agree with BHelm, except even if he does come back in November, he'll have to get back in game shape, so I don't really expect much from him the rest of the season. Sad. He was well on the way to 1000+ yds, along with Hilliard.
At the rate we're racking up key injuries only 3 weeks into the season we're not going to have much depth anywhere.