hi, i am a chinese,english is so so, so let me try to understand your meaning, the horse often was hurt by saddle, because high withers and narrow shoulders ,
we often met the same trouble, first, using double saddle pad,and fasten girth(two girth, frong and rear),
the second, change the gullet angle,readjust it by saddle maker,
my friend, made a pad with a hole in front the pad,
last time i got a saddle from usa, but most chinese horse narrow shoulder.
i havd to solve the same proble. you can email me email@example.com
i show you the pad