A word to the Tanks out there.

[Xariann]

A tank that marks the targets is average.
A tank that doesn't mark the targets is either really bad...
...or really good.

That's a good point, but also not a good point.

I have played with DPS who can't tell which mob to focus if there is no mark. So instead of taking the mobs one by one, they get taken down at the same time(ish). If it takes 45 seconds to kill a group of mobs (fictitious number), it's best for the healer to have the first mob die after 15, the second die after 30 and the third day after 45, than having all 3 mobs die at around 38-45 seconds.