Having a military background I suspected that the way the game last year changed in the second half that some type of intel was being used. IDK and it would be very tough to prove unless participants came forward. 
Today it was released that two of UM opponents have leveled accusations of scouting to steal signs and its being investigated by the NCAA. The same NCAA who has yet to decide what penalties Harbaugh deserves for cheating. Nothing will happen!

[Mod edit: Closing this. Already a staff article and two other threads about this.]