A question for anyone interested in saddle fit...

Riding style changes, the old saddles had no knee rolls so the saddles were developed to allow them, it has sort of gone full circle with the popular use of close contact saddles now, you can still buy half panel saddles mainly for use in the show ring. The reduction in load bearing is more questionable but at a guess it reflects people riding more quality types with a narrower top line rather than old fashioned hunters, cobs are more recent in popularity and saddles are developing all the time to suit the horses and job they are required for.
 
I'm not an expert in the history of saddlery but I'd say it was because of the invention of a certain Captain Caprilli:

http://en.wikipedia.org/wiki/Jumping_position

Saddles changed to reflect the rider's style and I think the panel shape change was a by product, though might have been deliberate. I fit lots of wide tricky horses and IMO we can get too bound up in "large weight bearing panels" above all else - on the wrong horse an overly large panel will cause instability, I think a stable fit with more constant pressure levels is much better than one which is moving and creating pressure spikes.
 
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