...However, my pony club manual shows all of the different saddles and mentions one called a "flat jumping saddle" that hardly has a pommel. It looks ideal. I'm going to ask next time I'm at the barn to see if they have one I can try out. :)
I'm mostly a western rider now, but I started English. I really think the solution isn't a saddle, but technique.
A saddle that rises rapidly to the front can be a problem, but most of those are western saddles. My Bates AP saddle is one of the flattest I've seen - all the English saddles I've seen have tended to be flatter than the average western.
An Aussie saddle is basically a dressage saddle with mickey mouse ears (poleys) to prevent forward movement. The poleys should be about a finger width in front of your thighs. The Australian stock saddle normally has a mild chair seat as well, but it is still easy for me to post in. That means my thighs don't move more than a finger forward - so posting does NOT put the family jewels much farther forward than sitting.
Even if your stirrups hang way in front of you - and they should not if your saddle fits - you shouldn't post from your stirrups. It should come from your thighs. I have to go by book reading, but it is my understanding that even with jumping, posting shouldn't put you way out of the saddle. Two point might, but the purpose of posting doesn't require standing in the stirrups.
I suspect the problem is related to gravity - the higher you go, the further to come down! And the further you 'fall', the more you hit - on both you AND the horse.
"Although, now that I think about it, and this probably doesn't make any sense, but when they had me posting without stirrups earlier this year I don't recall having any discomfort?"
That makes sense. Of course, my wife has never compared me to a stallion (and anyone comparing a man to a stallion would make me laugh uncontrollably), but posting light in the stirrups or without them doesn't get me high enough to have anything suspended above the saddle, waiting for an impact.
I played around with it this morning, riding in a western saddle that my daughter loves but that is NOT designed with a male in mind...didn't matter. I tried shortening the stirrups, and if I kept my heels mostly under me, it still didn't matter. The 'forward' motion of the post is relative to the ground, not the horse. The horse is moving forward with you.
My daughter's saddle:
I find it hard to believe any English saddle is less male friendly than that!
My Australian style saddle:
Not much room for forward motion of the thighs there! In fact, you might see if you could borrow an Aussie saddle & try posting in it...