When you look at modern 3-day eventers on their cross country phase, I think you will see a remarkable similarity of technique with General Patton's. In fact, notice the red on right/white on left flags along the jump. Methinks that the general (major/lt col/colonel at the time?) was participating in a 3 day event at the time the photo was taken.
Many (most?) eventers ride in a much less forward manner when going XC than they do in the stadium. And even then, both eventers and show jumpers almost never do stadium jumps in such an unbalance position as show hunters.
The jumper photo I posted is of the American show hunter discipline in which making the horse look as stylish as possible over jumps with the least amount of rider input is the goal. It is strictly a style show and the riders canter in a two point fwd position all over the course. Over the years show hunters have continued to deviate from the classical cross country jumping position to the extreme that you see today. It is educational to read older editions of George Morris' Hunt Seat Equitation and see how far from those positions show hunters in the US are today.
Honestly, I see little security in the modern show hunter style under stumbles or refusals.