Tiger has gotten way off track and into a swing method: He is stacking and tilting. This does not fit Tiger's body or the way he was taught as a kid. When we learn something that works and is natural, we shouldn't abandon it in an attempt to be perfect.
He used to have his right eye above his left at address, which allowed him to make a great turn. His eyes and head are now right over the ball, and his weight is a little left at address.
He used to keep the club nicely in front of his body. Now it comes too much inside and doesn't fit his bigger, more muscular chest.
As he goes back he tilts downward. This, of course, keeps his weight on his left anchor. That's not a good thing for a guy who has a bad left knee.
He is also much too flat for his natural swing and body type. On the backswing his shoulders are turning on a very steep angle, which artificially lifts his arms up.
He has always had great leg action, but with the new, lower swing, the arms can't catch up to his fast hips. This is a major mismatch. He leaves his arms and club behind his body.
At impact it has always looked as if his hips were open and his shoulders square. He has always had an underneath delivery pattern. This hasn't changed, and he will continue to hit the ball right on occasion and also hit a hook.
He continues to have a hold-on release, which also looks unnatural, causing him to lose clubhead speed. Tiger has gone from one of the most natural players on the planet to one of the most unnatural.