Why mark targets?

[YuriRamona]

However, marking is good because it gives DPS a focus and better for your own survivability. 1 mob at 10% health is going to do the same amount of damage as it would at 90% health, so it's better to go through one at a time (if you're not doing SRs and have AoE out the wazoo).

Well, obviously if you're at risk of dying then you should be doing a lot of things differently, including marking targets. However, every dungeon (with a few exceptions) is tuned so that the tank takes fairly minimal damage from enemy auto-attacks. The healer usually gets 8-12 seconds before a tank hits half HP, on average, by my estimation. Again, clearly if the tank fails to dodge, is undergeared, or inexperienced, my opinion doesn't apply.

Play Monk and then see if your opinion stays the same.

I don't see how it's all that different for Monk. Of course, you want to build Greased Lightning before using DoTs, but they have access to two DoTs that yield higher DPS than the standard combo, without risking losing GL stacks. Maybe I should have carved out an exception here since Monk's single-target damage without spread DoTs or AoE is about the same as another DPS class that spreads DoTs, so any extra damage is just icing on the cake.

Just mark mobs, stop being lazy. Put up a 1 at the very least (you can even be lazy and macro this to shield lob).

Attack the marked target, it's that simple, even cave man can do it, trust me, not hard.

This is the standard response I get when I tell people I will not mark targets and they should not focus down one target at a time and that they should try to use their DoTs. I've even explained how the maximizing of DoTs is superior damage and makes for a faster, easier run. Unless my fundamental understanding of numbers is wrong, marking and focusing one at a time is worse DPS.