Also, parsers are used for more than just calculating DPS. They're also used to look at who was using what buffs when. Like, if your Dragoon buddy keeps dieing to the missles on A1S, before you go screaming at the healers it's nice to know, did he have blood for blood up? did he use any defensives (Foresite, Keen Flurry, Second Wind)? Or what if no one caught who had that lightning debuff on T10 and wiped the raid? Parsers are invaluable. And using parsers doesn't mean you have to be a jerk about it either.