I am a strength and conditioning specialist. My subspecialty is injury prevention, and my focus within that is knees. This is my takeaway from watching Griffin this year. It's a good/bad scenario.
Robert Griffin has a movement issue that causes dynamic valgus stress in both knees. You could see it clearly in the strip fumble earlier in the season when he went down on both knees. You can see it clearly in his SUBWAY training commercial when he does the vertical jump.
What happens is that when his knee bends, through some weakness in the hip, or anatomical pattern, or ligamentous laxity, or pronation at the ankle or some combination of factors, the knee drifts inwards of the hip and foot. I.E. His final fall. This causes repeatd MCL/ACL stress and is a mess to deal with.
The good that will come of this, if there are any competent trainers in the Washington stable, is that the recovery from those ligament injuries will introduce him to the necessary stability exercises he should have been doing before. If this is not obsessively addressed, however, he will continue to have problems with his knees.