I'm pretty flexible, as I'm only 26 (not as flexible or strong as Tiger), but I let my right forearm match my spine angle at the top of my backswing. I can't see the benefit of pointing the right elbow straight at the ground like Tiger unless you want to dislocate your elbow. I'm not advocating a flying elbow, just somewhere in between the two extremes.
Thanks for the link to Tiger's swing. :cool: