When I tried it, I didn't stay with it very long because in my case, as soon as I started my draw it straightened out. There has to be something to it though, as some pretty high-powered people are recommending it.
Another thing that Clum recommends, that has worked for me, is to just touch my ring finger to the string on the pad rather than making it part of the deep hook with my index and middle fingers. This has eliminated any tendency I might have had to overload my ring finger.