I think the Gonzales brothers theory of "proper balanced movement" says
that the leg of the lower heeled foot is shorter that the clubby foot.
I think they believe there is a difference in the length of the bones.
I've heard several different theories on what causes high heel/low heel
and probably lots of them are true.
My horse has been shod for the last 5 years with a #2 wedge pad on the
lower heeled foot. The angles of the hooves and pasterns match. In his
first year of endurance he was starting to have problems with lameness
on the lower heeled foot. He has done more than 1000 endurance miles
shod this way and has done well. I do watch that foot like a hawk. He
had a quarter crack in it in 1995 that I attribute that to an irregular
growth ring (from colic surgery) that created a weak spot. If he is
going to lose a shoe it does tend to be that one (although he managed to
surprise me at Tevis last year by losing the RF and LR instead).
Overall, I am happy with this method of dealing with the high/low heel
problem. It has worked for this particular horse.
Judy Long and Nachi Sunshine (Warpaint)