I'm pretty sure it does interrupt their attack, but you have to basically be 3 inches deep in their butt before it interrupts their attack and "stumbles" them. And by that time, a smart player would have just kicked you.
Yes, exactly. The defensive shield nudge has pretty decent reach, that's why it should block projectiles during the animation and be the default opener for shielders to use against ranged. Otherwise there is no way to interrupt an archer/xbow/thrower without putting yourself at risk of being kicked.
