My position on this is that I agree that bosses rotating is frustrating when doing positionals. It is one thing when I can blame the tank for this, but when the game decides to "re-center" the boss and rotate it a lot, it is annoying.

I support positionals only making a minor difference to DPS. The reason for that is because min-maxers, people who truly care about min-maxing, will do them even for the 0.01% gain. But the large amount of people who can't do positionals or other job mechanics well, will not have a huge gap between their performance and that of the min-maxers.

Yes, there should be a gap between good players and bad players, but it's really not healthy for the good players to be doing double or triple the damage. That becomes a balancing nightmare, because then the content will die in 2.5 minutes for some and in 10 minutes for others. I miss stance dancing on tanks, for example, but I couldn't pretend it was healthy for the game for 50% of tanks to do over 20% less damage, probably among all the other differences between them like gearing, rotation competency, materia and food.