Spoken like a true baddie. Players like you make me lose faith in humanity. Nothing annoys me worse when I'm tanking a FP and DPS jump straight on the strongest mob leaving me to go hit all the others so that the healer doesn't die. If you didn't tunnel vision and did you're supposed to do, me and the healer's job would be a lot easier.
So you what? 3 man flashpoints with just one random dps? As for the healer dying I generally use "taunt" and/or a aoe to grab threat. As for hitting a "strong" given the gear and power creep a strong is merely the old "normal" and a dps can kill one during the course of a single ravage channel while tanks can simply 2 shot the normals.
Depending on team setup the most efficient strategies vary greatly, the "basics" are fine but are not always relevant especially in flashpoints which even in pugs are usually insanely simple.