Not sure whether I should post this in the lock forums but as there are other classes with similar abilities I'm sure I'll get more help here.
Will using my gosac shadowy bulwark on the pull add to my shield? For example SB adds 30% of my maximum health for a short duration, so if I pop it on the pull when our healers go ham for everyone's shields, will the shield take that extra 30% health I have at the time into account?