AST's weakness in end game

[TatoRazzino]

I'm sorry to say that, but your calculations don't make much sense. You're adding theorycraft to something that's situational and you didn't cover some basic things that AST brings to the table, like 10% AoE damage mitigation by using CU, which will also add a very powerful regen and doesn't cost any MP; also, you're ignoring Disable, which reduces damage by 10% and can stack with Virus/cover the damage when SCH's Virus is on cooldowm; you're also assuming that the AST will keep Aspected Benefic up 100% of the time, which is not necessary due to the initial burst healing/lower cooldowm on Essential Dignity, which reduces a lot of the healing burden on AST. And I didn't even mention the fact that any Bole used on the tank/party can reduce damage taken. It was a nice effort, but the playstyle you describe for AST is not that of an AST, it's that of a WHM. If you behave as WHM when playing AST, you'll always lose.
Even for WHM, which uses Cure III a lot in that fight. I don't think the metric you used is good for any conclusion about what you're trying to analyze. But again, nice effort.