It seems that in groups in this game the role that has the most impact on the groups overall DPS is the healers?

In 4 mans, 8 mans or 24 mans, the difference between "good" dps and amazing DPS is noticeable, but actually that huge of a difference.

The difference between a healers who DPS and the healers who don't makes the whole group feel different. Things start to die really fast and it's like "oh it's a healer who actually uses cleric stance"'

Then you get those Syrcus tower groups where Amon dies before Curtain call, you look at the raid after and see like 6-7 healers in cleric stance and it's like "oh, that's why."

Not that DPS doesn't make a difference, but it seems like if you really want to put a huge difference pace you should play a healer who actually knows how to DPS.