I haven't done much testing regarding the energy absorption et al, however, when I'm attacking and a shield bash goes off - with my character sheet open - the orb bonus (from the purple dragon shield) to my saves and resistances do get applied appropriately while the shield bash takes place... However, the buff icons for the various actively blocking feats and vanguard, etc, do not appear.
But for me, when I can see something coming (like Velah's fire breath, ballista fire from storm the beaches, magefire cannons from precious cargo, any placed explosive that I don't have time to run from), I will actively block to take the hit, and I'll either take barely any damage or no damage at all, so yay! (as a direct answer to the OP's initial question: Yes, I do use the Shield Deflection feat).
It would be very sweet it they would activate while making a shield bash though, like the dragon shield orb bonuses do. *dares to dream*