The story of the fragile tank:
I was playing my Commando as a healer, and we got into Athiss at 55 hard mode with this Guardian tank. He had around 35k HP, and on inspection, seemed to have a pretty impressive Elite set with augs.
Then during actual fight, his HP bar starts waltzing up and down and it's all I can to make him survive. After finishing one mob, I examined his set and found everything was in dire need of repair. Who goes around with their armor durability at 75/120? So I pulled out my repair bot and told him to go ahead and fix it. He didn't. He remains a silent sphinx throughout, and on top of it went total LEEEROY on every mob that appeared. After the 5th time the whole party was defeated, I decided to call it quits.