Originally Posted by
DevilsDontFly
While I do see your point that still doesn't tell if you individually is getting better at your dps rotation. It tells you're getting better at not being dead.
And even if you play regularly with the same people, that still doesn't mean you as an individual is pulling the numbers you're supposed to in order to progress a fight. This I say from experience, because I've been in many groups in which someone would execute mechanics flawlessly but still not be very good at their own class rotation to the point of severely underperforming. And when someone underperforms, someone else has to make up for it. A party being able to clear content, it being fast or slow, does not mean in any way, shape or form that all 8 players are on the same skill level. Not without numbers to back it up.
I was also on the other side of that same perspective, thinking that I was a really good DPS throughout fights when in reality I was being mediocre at best.