I think there's a fine line between efficiency and obsession, as Hayward said. I see nothing wrong with wanting to maximize your DPS or your role as a healer or tank. But, at the same time, I've been in parties where people would call out the DPS of a tank while we were still having aggro problems.
I think we should first worry about people functioning in their respective roles before we worry about maximizing the potential of every class/job. I know this game has some very steep DPS-checks, but I'm seeing quite a lot of tanks and healers letting other parties members die because they're too busy trying to maximize DPS instead of tanking or healing.
Exactly. I'm a MCH, but I was previously maining WHM. I don't have Blood for Blood. I'm working on it now so that I can maximize my DPS, but I'm not going to pull my hair out over it. For me, personally, I just won't raid Alexander Savage or anything with very steep DPS checks when I know I might not be able to make it. Everything else is fair game, in my opinion.