Kinda sounds like you'd understand this already, but we've all seen it come up once or twice, so maybe worth saying: Flash isn't a long range spell.

Like I said, I'm going with the assumption that you seem to sorta know pretty well how to catch aggro and all, but, yeah. Eventually we all get stuck with the tank that uses Flash way too early for it to actually hit anything. But if you're holding onto everything, then you're probably not one of those.

As much as any of those knobs complain, guaranteed we've all seen worse.