Shoot, he could ride!
I have a calendar from the RR Ranch that says Dutch preferred to ride English.
Why? President Reagan usually rode in a forward seat (English) hunting saddle. You can see the knee rolls in the shot of him on the white horse.
The caisson unit uses an Army pattern officer's saddle (as opposed to the enlisted men's saddle, which was the McClellan until fairly recently unless they were participating in a drill squad or jumping.) It has a cutback pommel, very high cantle and deep seat, and a straight flap with a slight knee roll. The stirrups are mounted further back than in a forward seat saddle, and when it's ridden in it's with a very straight leg.
You can see all this in the picture if you look closely.
My dad was in the next-to-last active troop of the 2nd Cavalry Div. at Fort Clark TX. That's where he learned to ride, he had never been on a horse until he showed up.
That's english
Your picture is of an english saddle. Reagan rode western a lot, but the picture he is using an english sadddle.
Nancy rides western, if she still rides.
That photo hangs proudly on my wall about 10 feet from the computer I'm posting on. Wonderful shot, isn't it?
For years, I had a print of that photo up in my home office. It only came down this March, when I moved.