Well I only have castle shield, but it allows me to attack and move albeit it's a little slower than usual to start but I do attack and kill stuff with it active.
and its apearently helpfull in pvp
so how come i never seen any bladers/swords using it during pvp? i belive that if i was a nuker i would take the few secs to give myself another 15 secs of 408 phy def