"You won't know you make mistakes and how to fix them without ACT"
If you are solely using the tools the game provides you, and not reading any job guides, then this is just true. But it still doesn't make it mandatory, people can make plenty of mistakes and still clear content. My static is very midcore, I make plenty mistakes, as does everyone else in my group. We're almost done with the tier. Again, as long as you find a group that has the same expectations, nobody is going to expect you to have any addon.

In addition the the above, savage and even ultimate fights can be cleared via the Party Finder in game. Nobody in any PF group has ever asked me if I have mods, or any such thing relating to them. And I have played REALLY badly in some groups, causing wipes in several instances and doing really bad damage. The only person who ever criticized me for those poor performances, was myself, as it should be. So in the end, I hope this clears up some of the misconceptions and allays some of your concerns you might have surrounding the topic, and explains why some of us feel the way we do, and think that people such as Johners are being particularly spiteful. I know that the culture in WoW regarding addons is atrocious - I've been through GearScore, Raider.io, DBM and I genuinely hated it all, but that doesn't mean that XIV cannot be any different. We just have to ensure that toxic behavior using the addons is not allowed, but that doesn't mean the addons themselves are to blame. Chances are someone who would flame you for low DPS will just find any other reason to flame you anyway. They can catch a ban.

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