Which is an easier downswing thought?

Check out Fred Couples swing below. I do not see what GG teaches in Fred's swing, or a "sink down" movement. While I understand the sink down and subsequent push off of the ground increases power, in my opinion that introduces the need to control an additional vertical movement component. A little sink, maybe, but it won't be much more than an inch for most folks. Even then, I'm not sure the benefit of adding a sink move for a few more yards is worth complicating a swing given folks already struggle by employing the fewest movements possible.

Plus, GG teaches to unwind from the trail foot while Couples weight has already moved to his lead foot at the start of the downswing.

Finally, the "lead hip low or neutral" is capturing a millisecond moment in time because the lead hip will rotate left and up, so I'm not sure why GG thinks this is unique. The only thing I can think of is he teaches folks the traditional shift into the trail foot on the backswing, then shift to the lead foot to start the downswing. In that case the concern over the lead hip being neutral makes sense because people have more of a chance to swing off their trail foot (right sided swing) and thus their lead hip travels up to start the downswing. But in SnT the weight is more on the lead side at the top, thus the trail hip will travel up during the backswing. Then as the club comes down the hips will be neutral for a split second then travel left and up (lead side extension).