Ok, i posted this on the spin-off thread about sticky stuff:
After reading the rule book, and another COTH thread about IHSA, this is what I found:
4700: Tack and Aids
4701 Neither substitution of tack or aids nor addition of materials by exhibitors which could affect horse or tack shall be permitted unless approved by show management, or per Rule 1400.
(Bold was my doing)
After reading the other thread where mention was made of a horse’s skin being rubbed raw from use of sticky stuff, I think this rule could be interpreted to include no sticky stuff. Anyone who has used it knows the residue that gets left on saddles and horses’ hair, and has also most likely come away with hair stuck on their boots.
So instead of it not being allowed because it would enhance rider position, perhaps this is why most (all?) schools don’t allow it. Again, just my interpretation.
So it doesn’t answer your question about these boots in particular. Now that I have read the rule book, and made that interpretation, it seems that these rubber grips would be allowed, as long as your coach is ok with it.