Far more than just a damage meter. It's rather a desire for a more comprehensive measure for player performance. Alot more goes into pulling off those BIG DEEPS than just hitting buttons good. Buff alignment, group mit so healers can more effectively dps, minimizing deaths/debuffs, tanks understanding boss movement speed and facing after mechanics to allow dps to squeeze out positionals more easily, dps taking the opportunity to get in these positionals, etc...
