Saddle nerd and stubben user here but not affiliated with any brand and not a professional fitter. Yes stubbens are designed to bridge, slightly, it’s in their tree construction you can see their “naked” trees and the saddles flex in hand without undue effort, it is not just fancy marketing it is Avery valid and valuable design that many horses love, however, I have less faith that every fitter will respect the design and not use it as an excuse to ignore bridging issues. You should see a little bit of air when you put the saddle on, girthed up and with a rider, a correctly flocked/fitted stubben will no longer show bridging. Over an inch sounds like your fitter is relying on that design aspect too much as a bit of an excuse. It should be slight bridging, not over an inch like you are describing. When you have the saddle girthed up, do you still see air through it? Are you using any half pad? Also the spring tree is not the same as a standard flexible tree, the construction is different and materials used as well. If the flocking is new and hasn’t compressed (takes 20hrs saddle time to compress new wool panels for stubbens) it is another aspect of whether or not the saddle fits/will fit appropriately.
If she said it doesn’t matter how much the saddle bridges just because its a stubben and has a spring tree, that is wrong, if it bridges a lot, you will over flex the spring tree, compromising its integrity and more than likely create a sore back with use. It sounds like what you are describing is excessive and I would hesitate to use the saddle personally without a flocking adjustment to minimize the bridging to an appropriate amount if the rest of the saddle works. I do not know how foam panels on a stubben work with their spring tree, I have experience only with wool panels which change and foam won’t, I would imagine if the panels are foam you would want even less/if any bridging than what is acceptable in a wool panel saddle. I hope this helps and you get your question answered!
