Meters and/or logs and/or analysis tools for logs are all useful and important tools for self-improvement. I don't run them myself, but I definitely look up my character on log sites because a lot of folks upload logs and it's useful to know how much mustard I'm cutting.

I'm still not sure that I want such tools to be officially endorsed, because I remember what WoW is like. I like that you're not supposed to talk about parses in pick-up groups, and I can't think of any way to officially implement a parsing system (because that's what's important - comparing your output to a statistical body of people doing the same fight on the same class with ideally similar level gear) that wouldn't cause people to bring it up. Rules or no rules, if it's officially supported then people will assume it's fair game to put people on blast. I don't want to see that; down that path lies madness (or at least a much more hostile environment).