Cleric Stance is actually a very nice skill for both CNJ/WHM/SCH.
The only way it is viable though is if you use MND as your primary stat. Switch MND into INT stat and you can dps with a 10% increase in damage. Yes, you do 20% less healing but Cleric Stance is used to put a Healer class into a dps mode. Cleric stance also doesn't follow the GCD and to remove it has no animation so you can easily switch back into healing mode in an instance. In CBT I played CNJ a lot and I was very pleased with how they could change to damage or healer so quickly.

Cleric stance for SCH would be amazing but only as long as they make MND their primary stat. I view scholar as a DPS that CAN heal. They still get all of ARC dps skills - just more heals added on. Cleric Stance would be great for them.

Also, fun fact, the game considers Piety to be main stat of Scholar. When a SCH joins a party, the PIE highlights in the party limit break menu. I found it interesting.