Pre 2.0 yes... but not sure if was all the way back to 1.4 LOL. But yeah at one point, 2 blues stacked no matter of class. So you could have 2 poms or 2 tos or 2 shammy. I'm thinking this was pre 1.05 because it was when we had less HP and the healers freaked out and said Healing was gimped because now guys had more HP and our heals were less effective.