Invulns: Problems and Solutions

[Ultimatecalibur]

Fair to a point, but I find I often use them in order to explicitly avoid learning scary mechanics.

Pretty much. When most high-end players talk about using invulns to cheese mechanics they are more often than not talking about the use of them to simplify complex or tightly timed mechanics.

Tankbuster that requires a tank swap in the middle to handle as intended? Invuln it and do the tanks swap at a more opportune time.
OT and DpS need to juggle a tether? Let the tank take all the damage from the tether with their invuln.
Stack mark on a Tank? Invuln it so everyone else can focus more on dps than stacking.