Granted, you'd have to be really far into the progression AND really bored to do this, but in 2.4 - where T6 has 8 pieces but the bonuses are still 4-piece - could you theoretically have a dreamstate hybrid build in which the person is in "full T6" for both healing and DPSing at the same time? 5% bonus to HT, as well as starfire crit bonus...seems to be a dreamstate's...well, dream.