All I know is what I saw. Too many times I saw him for no reason vacate his gap to hide behind a DL and leave a gaping hole for the RB. Then he would run and chase and jump on the pile after the RB was already down. It happened too often for me to explain it any other way than he was doing it on purpose to avoid having to meet the RB head up in the hole. Yes, he also had poor instincts and was slow to diagnose plays but that was from day one. Something happened that last year or two that had him running around avoiding contact.