That video is from about 3 months ago. I also found one from Saturday at the Memorial -- interestingly, Jack Nicklaus makes reference to the Peter Kostis commentary from the above video... and disagrees:
I want to call your attention to several aspects of Rickie's swing.
- I've talked about microsquats (for righties and lefties) before -- a very slight squatting action that allows you to keep your upper body from sliding away from the target because it relieves some of the tension on your back. You can see this in both of the videos. Rickie's hat moves downward slightly as he turns; this is especially important since both his feet stay pretty flat on the ground.
- Kostis mentions Rickie's weak right hand position. Notice that it's only his right hand. Although it's unusual, you don't have to set both of your hands at the same angle. Rickie's left hand appears to be in a neutral position, which means if you stood in front of him (as in the first video) and he lifted his arms and opened his hands so his fingers pointed toward you, they would form an angle like this: /|. Most people would put them together like this \\ (a strong right-hand grip) or this || (a neutral grip). I'm right-handed and sometimes use a grip like this |\ (a neutral right hand and a slightly strong left hand) when I'm having trouble squaring up at impact.
- Rickie has a really good upper body coil by the time his left arm is parallel to the ground. That's how it should be, people; although his shoulders continue to turn a little, that halfway point is when your coil is mostly finished. The rest of the swing to the top comes primarily from your elbow bending (in this case, Rickie's right elbow). His hips have turned some, but not as much as his shoulders. This is a move you can practice with pitch shots; it can be a little uncomfortable at first, but this is a low-strain way to learn it.
- His wrists are about halfway cocked at that halfway point; this is a good compromise between a "one-piece takeaway" (where the club is almost parallel to the ground at this point) and an "early set" (where the wrists are completely cocked). This is an area where teachers disagree; Michael Breed, for instance, likes that early set, as did my teacher Carl Rabito. But there's nothing extreme here. As strange as Rickie's swing may look, for the most part his movements are pretty normal.
- At the top you can see the "secret move" at work. Rickie has laid the club off, but watch how much the club drops down behind his head, which is that sideways motion I mentioned with the two-plane loop and two-plane tilt posts. His swing is very flat, so he gets this action simply by dropping his right elbow down close to his side. This drop delays the uncocking of his wrists until he's halfway down again -- which means lots of power.
- The last thing I want to mention is his legs. Jack is right; Peter is wrong. While Rickie's hips and legs do start the downswing (no matter how you swing, they have to -- it's simple mechanics), they stop before they completely unwind. I can say that with certainty because his right leg is straight and his right foot remains flat on the ground through the hitting area. Unless that leg is made of stretchy stuff, those hips have to stop! But that's fine; it helps Rickie be more accurate. After the ball is gone and his upper body has turned on through, it pulls his hips the rest of the way into his finish.