For a student, I traced out a little "flow" trace or "COM" trace. It's exaggerated in scale, but I think it's fairly representative of what a good player's "feel" is mixed with a bit of the common reality.
When I was done, it looked to me like the Vineyard Vines whale, so I drew a little tail on it. Here it is:
1, 2, 3, and 4 are A1 through A4 (or Ps if you still prefer those).
- At A1, the pressure is pretty centered.
- At A2, the pressure has just about reached the farthest back position after a slight shift toward the trail ankle. That shift is almost entirely done by 2.
- From A2 to A3, the ribs and torso "wind up" and the feeling is of a rising COM (even though nothing really goes "up" much except the arms). This is the part where you're "flinging" the club and arms and hands the most.
- From A3 to A4, the body starts to re-center by "backing into" the target. It may have only shifted an inch or so back (the scale of the whale is greatly exaggerated). The lead knee stays soft so the player can "compress" a bit before they "jump".
- As the downswing begins and continues, the pressure shifts down and forward until it spikes back up just before impact. The tail is somewhere around impact - slightly before or after depending on the player. Everything, of course, from the "4" to the "tail" happens very quickly.
Of course, it's not quite like the VV whale as I drew it, because he has a relatively flat back, and I was trying to emphasize for this player the "soft left knee" so I drew the trace a bit more "down" from A3 to A4. I've used the Leaning Tower of Pisa before for the 3-4 stage, or the feeling you have of pushing water back and forth in a bathtub when you're a kid, but this is the first time I'd drawn it out this way. For some players, the flatter (more horizontal) back of the VV whale may be a better feel, but overall, maybe thinking of this logo will improve your "flow" a bit.