So I was looking at discipline priest and I was thinking, wouldn't it be cool that priest could tank by abusing bubbles. This in my opinion could make for a unique tank, where instead of dodging and blocking, priest must use their bubble to mitigate damage. Of course this would make healing confusing, so a passive would be added to help them out. So here is how I think a priest tank would go.
1. Mastery: Holy Shield - 10% of all overhealing done to the priest would transform into a shield capping at 100,000(+15,000 per 1 mastery) damage absorb. This way, the shield cannot be healed to the point where it becomes impossible to take off.
2. Super squishy: As a priest and clothy, you are super squishy, the moment your shield collapses, you would not last long. Meaning, keep your shield up or you are a goner.
3. Buff management: as stated before your bubble is your only means of survival, so the spec should tailor to making your bubble as sturdy as possible, Firstly, each point of damage done by the priest reduces the cooldown of Power word:Shield by 1 second. New Passive: Infused light - If you cast powerword:shield with another shield already active on your character, increase the damage and duration of your current shield. Also, when outside combat, place a powerword shield at maximum absorb that last until attacked.
This is a work in progress, but tell me what you think