Geeezzus Tiger, I could tell ya what your doing wrong, so I have no idea what this new unheard of swing coach of yours thinks...you need to go back to the drawing board dude...oh, and stop swinging so frickin hard, and play more golf.
I think his biggest problem by far is his putting. Unbelievable how many putts inside 15 he missed this weekend. He missed some gimmies. His putting put him in the hole and he tried to force it most of today.
He was putting very well before the weekend then as gip said, they stopped going in. That and he can't dial in his irons like he used to be able. He's always been wild off the tee but his recovery skills with creative iron shots was off the charts, not any more. Still one of the best players in the game, as evidenced by 3 tour wins this year.
His personal problems created self-doubt while at the same time exposing his vulnerability to his opponents. The former is at the root of all his problems on the course in my opinion. The irony is he is still playing better than most and seems to be on the leader board every week.
BTW about the swing changes...I'm fairly certain that he had no choice. The swing that allowed him to dominate golf like no one else also had a nasty effect on his legs to the point that he had to change the swing or limp off into the sunset.