When actively blocking with Block Energy active, my + tab shows a 21% absorption increase, not 30%. Displayed numbers go from 30% to 51%. It's not maxing out my absorb, since the absorb numbers go higher still if I equip e.g. greensteel absorption items.
I'm curious if other people see this on their toons, and whether this is a display bug or an actual error in the amount of protection given.