Amp on dice boss shield

suggestionman#1119

I've heard ppl saying that amping the DDH dice boss while he's shielded has no effect and other ppl saying the opposite.
I've never had the opportunity to test since there's always someone else hitting the boss.
Which is true ?

npc15

I'm pretty sure any amps during the shield phase cause it to knock more off the shield, but still do 1 damage to him, because youll do more damage but itll all go towards knocking the shield down