I think it was the form of the team. I think the failure of the team played with his head and he tried too hard at times.
Everyone knows that sport is a fickle mistress and trying too hard can be as bad as not trying at all.
There were games where he would rush in at a million miles an hour to tackle or over think his catches on the ball. There were comparatively easy skills he would stuff up when the team was down.
Those 3 on 2 sweeps on the other hand were damn hard yet he could do them in his sleep. He didnt have to think doing them and the team was on the up. Add the problems or injury and his was a sad spiral. When you think of his best games there were against teams the broncos weren't expected to win whilst his worst was when the team was flat.
I don't know if he will make the side round 1 or if he does he will capture his glory days, but I'm confident he can be a lot better player than last year.