Call me crazy, but I'm going to take one more whack at this.
I'm sorry but I just don't understand your reasoning. I see my domino and puffer swim VERY quickly across the tank sometimes; does that mean they too "need" a huge tank that relatively few can afford? What if I became a "Pomacentrid Police" and belittled anyone who didn't keep them in a monster tank, and then when asked why, couldn't even explain my thinking let alone defend it with factual information?
You: "Hello all, I think their may be something wrong with my coral, here's a picture to help identify the problem. Thanks in advance.
"
Me: "Dude you should really move those ocellarises, they need a WAY bigger tank and by keeping them in yours you are being cruel to innocent creatures, they may be fine now but give them a week and they'll be dying/dead."
You: "I've had them for a long time in here and other people keep them in tanks this small with no problems. They don't swim fast or anything, so why do you say they need a bigger tank?"
Me: "I've seen them in small tanks before, and I said to myself "these things need more space". It's just the way they swim."
Another person: "That's bull, they will be fine in that tank, many people have done it, (insert tsunami of reasoning and proof against "Me's" attack here). Also, your coral is simply collapsing, will be better tomorrow."
Me: "I don't care what you say it's my rule. Nothing you can say or do will make me change my mind. I have no reason to believe what I do and hardly the right to force it on others but I do it anyway. Yes I know I'm arrogant, ignorant, stubborn, and insane but I don't care what you say."
Just scale up the tank sizes and change the fish, and you've pretty much got tang police.
Sounds pretty psycho when someone put's it like that, huh? At least change the avatar for Christ's sakes.