I feel your pain. Dancer is short backed, downhill and high withered - with the same broad shoulders. Fortunately, she doesn't buck when the saddle bothers her - she just puts up with it until she's had enough, then refuses to move. Up until that point, there is no way to tell she's uncomfortable, which really makes me feel bad. Add into the mix the fact that I am an extemely plus sized rider, and finding a saddle to fit her is even more important.
And... a crupper is out of the question. Tried that once - she went ballistic!
I am going to try the wither tracing thing as soon as I have the money, and have a saddle guru pick one out for us...
Plain Old Dee, horses Dancer and Rain I believe in dragons, unicorns, good men and other mythical creatures!