Removing Cleric Buffs

So I've spent a lot of time understanding the nuances of arcane magic (especially for SCS) and the chess match involved in protecting and removing mage buffs. Then I thought of priests. In SCS (or even vanilla) are they completely screwed?

If I buff a cleric up with many of his protections, would a mage (especially a SCS one) just throw a dispel magic my way and remove all cleric buffs? If so, is there any way to protect them?

Lastly, is dispel/remove magic the only way to remove priest buffs?

Thanks in advance!