This might sound like a stupid question, but I wanted an answer from the forums on what is the proper way to choose a target as a DPS? Should I just pick a target unless the tank has one marked, unless it's a situation like the bee's in Qarn or the maids in Haukke manor?

I've been running most of the game as a tanking class. As I started running the mid level dungeons (roughly Haukke Manor to DD) I noticed that some dps would pick a target to strike down when pulling trash. It was often a separate target than the one I chose, but it didn't matter much because holding aggro became rather simple. Yet if I'm going to be running dungeon's in another role I'd like to know what the generally proper way to go about it is from the community?

As a side note I do not usually mark targets since I play with a controller and have limited button space and my fingers aren't really nimble enough to jump between attacks and marking.