livestoride - just because you have a saddle that has the changeable gullets, does not mean that the saddle will beable to change to accomodate the horses shapes.
All the gullet change system does, is change the size of the tree - nothing more, nothing less. They make the saddle wide, medium wide etc, etc - you get the gyst :)
That does NOT change the gullet channel, the shape of the panels, the way the panels rest on the horses back, the shape of the tree *flat, or arched*, the length of the saddle and etc, etc.
Horses do change shape often, take my TB as an example - he either gains muscle on his topline, or loses it - which does dramatically alter how the saddle fits.
That is why, having a professional to help you, is a good thing. Every 6 months, you should have your saddle assessed by a professional.
If you use the horse as your chair while you chat with someone and don't allow him to move, that is when he will become sore.
Yes and No. A) It isn't a good idea to sit on your horses back to sit around and watch classes that you aren't involved in, or to sit around to chat with friends for periods of time - because you should give your horses back breaks at any possible time. The only time you should be standing around doing nothing, is when you are off your horse.
BUT on that note, an ill fitted saddle will do serious damage to your horses back. Whether that saddle is an "ok" fit, or a poor fit - no matter what you are doing when that saddle is on their back, will result in serious back pain if allowed to go on for long periods of time.
Our horses show us signs of pain, from ears pinning back, tails swishing, not being able to get infront of their riders legs, girth, biting the air or you when you put the saddle on, ansy when tacking up, not moving forward, bucking, rearing - to back pain when you palpate the back, from loin, center of the back to withers.
For example, my friends horse is very honest and does anything his rider asks of him. He shows signs of ill saddle fit, not through performance, but through signs when on the ground. He is sore in his loin area when you palpate his back, slightly in his withers, and when you put the saddle on him and start to girth him up, his ears pin back and he bites at you - DING DING DING..poor saddle fit.