After serious experimentation I don’t think that this issue is related to their setup or logic at all…I think it’s an unavoidable side-effect of transition animations since they aren’t loop-able.
I say this because when I setup all this logic on state machines running simple Sequence Player Animations the issue was still there…even after removing Orientation Warping and Stride Warping from them. This seems to indicate that you can’t have transition animations without pose popping during key spamming.