Be quiet XyNox, or you will be burned here, on this infantry forum.
It requires huge skill to use right mouse button as shielder, it takes ages to learn it! You need to spot right moment to press it, and that's huge challenge. Press right mouse button or not press it, that's a question. It's obviously hardest for shielder to block arrows/bolts/throwings/swings/thrusts/even couch, because you have to press that right mouse button, and that's the hard part. Shielder is of course hardest class to play, it's very hard to master right mouse button blocking everything you can think of.
Praise the mighty shielders!