When you look at pics of horses really snapping up in front over a fence their feet are nearly always infront of the area the stud girth protects so why doesn't the girth cover that bit too?
It physically can't without impeding the movement. I have looked at this because my mare will sometimes stud herself in front of the girth. What some people do is put sheepskin around the brestplate / martingale that attaches to the girth to give extra protection.
I think this too - I always wonder why people wear them as when I horse snaps up it goes up into its shoulder and not near a stud girth.
Its for this reason I have never bothered to have one - but will do now as I am getting a single flap saddle and most of the girths are short stud girths. I spose its like over girths and greese not a necessity (sp) really but could help
I use one as a precaution as G needs to encouragement to loose confidence, and he is neat infront. As SJ has said though, it has got several mrks on it where he has caught himself, so pleased have had it on! Although I think a wide thick girth would prob do the same trick tbh.