I'm not entirely sure on other DPS but I tend to be quite forgiving on tanks as a BLM. If I pull hate cos a tank has a slip up I just use manawall or manaward and its fine.

The way it should be, is that if the tank makes a mistake (which everyone does) the other classes can use an "oh shi*!" Skill resulting in a minor hiccup and not a wipe. Again I know BLM have good defensive skills as a DPS not sure about others.