To be honest, the only time I get annoyed/angry as a Healer, is when the tank is utter garbage.

Due to being a Tank main with many years of playing Tank, it really annoys me to no end when I see Tanks being played wrong (Mistakes are fine, to err is to be human. But playing them straight up wrong hurts my soul...)

Though, ShB healing is so dull... It is honestly difficult to actually level my healers because of just how attrocious the gameplay is...

Dungeons are: Regen/Aspected Benefic > Holy/Gravity/Art of War times infinity.
Bosses are: Bio/Dia/Combust > Broil/Glare/Malefic times infinity.

Occasionally, press an oGCD heal for the Tankbuster/Raidbuster. But otherwise, mash 1 button hundreds of times...

It's even worse in a Trust, where Thancred is so OP that he doesn't need heals because his Brutal Shell heals him like 50% of his max health and gives him an equivalent shield and you're there doing pitiful DPS while both Trust DPS are using single target attacks through all the trash (When they're not standing around with a thumb up their rear end because a mob used an AoE)...

Like I though Tanking in Trusts was bad, but at least you have to dodge AoEs and can use CD's to mitigate damage. As well as having a rotation that isn't just a single button (Though, I admit, the 2 button AoE "Rotations" are not far off...)