40% Critt i would assume is kind of a softcap for hunters, since then you are at 100% with rapid fire / target at 80% hp. It obviously doesn't become useless after 40% and is probably better then mastery or versatility.
But multistrike tho, would it be better to gem for multistrike when you hit 40% critt chance? I would think so, haven't tested it obviously but still.
Opinions?