In-Game Parser.

[Lycelle]

DPS checks are like tug of war.

8 People against 1 big man. If all 8 people are pulling, you can pull that big man into the mud. However that big man is strong and can pull all of you, however if everyone pulls their own weight you can resist the pull and manage to pull back twice as hard. That's what a DPS check is, it's a tug of war between DPS and the boss and if you can't do that as a group, then you're going to fail. A parser is nothing more than a tool to spot a weak chain. You cannot blame a parser for how it is used, simply because it is a in itself a glorified calculator. You can however blame the approach made towards the effort to help someone improve their DPS. It's the attitude that matters when you become the bearer of bad news.

Raid Leader Don: Hey. Great job tonight guys, we're gonna however have to try harder. We keep failing the DPS check. Why is that? Let's take a look at the data here and see what we can find.

The raid leader goes though the parsing information.

Raid Leader Don: Amy. Good job on Monk. You were top DPS! Pulling 430
Amy:
Raider Leader Don: Anthony, excellent job on Summoner. Pulling in at 398
Anthony: Hell yeah!
Raid Leader Don: Jackson. You were a bit low tonight, but you still did good as Bard tonight, that song really helped us though,336. Could do for improvement but still good job.
Jackson: Alright. I'll have to work on my rotation and dodging mechanics. I did die so that's my fault, but I can fix it.
Raid Leader Don: Maggie...honey. You were the lowest DPS tonight. What do you think you're doing wrong in your rotation? Your Dragoon did so well last raid, but right now your only clocking in at 297.
Maggie: I'm not sure. I think when Blood for Blood is up and I died, I lost DPS that much is for sure. But I think my rotational is off during some of the mechanics so I lost DPS as well. Sorry I'll work with Jackson next week and we can practice. That sound cool Jackson?
Jackson: Sure. Sounds good to me.
Raid Leader Don: Awesome! Good job tonight guys, let's shoot for improvement next week. Try to cap your Tomes and get a piece in if you can, that'll help too.

This is the kind of motivation a parser can bring if used correctly. There are a number of reasons "why" DPS numbers CAN be low and hold a group back, but that is where a parser is used. It is used to figure out what is going wrong, whether it be mechanics, rotation issues or gear not being up to par in terms of BiS. All it does is take what is already there in the Battle Log and cuts out all the fluff and gives the raw numbers. So if you want to really be technical, the game "has" a built in parser called your Battle Log. You can sift through it, pull out all the numbers and crunch them. Sure it will take you awhile, but it's the same thing as using a parser, except the Battle Log tells you everything that happens, and a parser just simplifies it for you to read. Nothing more nothing less.