Girths / Half Back Pads
I recently had a saddle fitting done using an electronic pad that was placed under the saddle. It displayed areas of pressure on a computer monitor. The most interesting and surprizing thing that I learned didn't even have to do with my saddle! What I noticed was that there was a high amount of pressure on every scan where the girth was. I learned that the kind of girth that so many of us have always used, those contoured leather girths with elastic on one side and a thin strip of leather in the middle are really uncomfortable! Girths with leather that goes all the way across the width of the girth, often called 'overlay' girths, are much better because they distribute the pressure across more area, reducing the amount of pressure the horse feels. Also, having elastic on both ends instead of just one helps greatly, because the pressure is distributed evenly onto both sides of the horse, instead of being concentrated on one side. Makes sense.

I also found out that those wildly popular 'half back pads' (also known as 'wither relief pads') actually increase the amount of pressure on the horse's withers, instead of decreasing it, as they claim! Who knew!