"He even says he can tell when someone is using a parser or not, because a person using a parser goes full bore right off the bat to try to hit the biggest numbers they can."
The only class that actually needs to do that for optimal damage is RDM. For any other class, that would actually not get you "the biggest numbers" and would be bad dps, which people with parsers usually avoid. The people that rip aggro off in the first 3 seconds(bar RDM) just think they're doing so good since they pulled hate...even though the tank hasn't had any time to establish aggro. Those kinds of people just THINK they're good and almost certaintly do not parse.