Hollow wrote:Rainbow Dash being an arrogant vain cockbag to just about every single pony = fine
The rest of the main cast being jerks to Rainbow Dash to teach her that she's being a fatheaded egotistical prick = not fine
What kind of logic is this?

Except that's
not what actually happened. They didn't teach her to stop being a fatheaded egotistical prick by being jerks to her, they taught her that it's important to be humble by... well, really, by sitting down and talking to her about it. The show presents the Mare-Do-Well scheme as being the reason Dash learns her lesson, but ultimately what really happens is Twilight goes "it's important to act with grace and humility" and Rainbow says "ooooooh now I get it

"
And really, the main thing that bothers me is that while the show recognizes RD is being a jerk, it doesn't seem to realize that the others are, too. It may be that what we're supposed to take away from it is 'they were being jerks in order to teach Dash not to be a jerk,' but the way it's presented doesn't really seem like that to me.
Hollow wrote:Really though, have you ever been in a fight with a significant other or a good friend, and you can't seem to get the point across to them until you act like them? Then they realize "wow, I was pretty awful" or just get more defensive and stupid.This is the same concept.
In my experience, that kind of thing very rarely works the way it's intended to and almost always ends up leading to the 'more defensive and stupid' outcome. When you get down to it, directly confronting somebody with your problems is a much more effective means of conflict resolution.
Of course, that doesn't make for interesting television, and I'm not saying that it's a bad thing they went for the angle they did; I just feel like the way the story was presented made the characters' actions seem oddly passive-aggressive in a way that kind of bothers me.
Edit:
Tallgeese wrote:It WOULD have been malicious in the event that they explicitly said something like "If only a CERTAIN OTHER PONY were like Mare-Do-Well!", but this did not happen thankfully. The Mane Six basically did it in the nicest way possible. There's also really no evidence that Rainbow Dash would have figured it out by just being told about it, considering that she explicitly denied her jealousy until the last second.
They never directly said anything like that, true, but I feel like the of sentiment is definitely implicit in the conversation.
And you're likely right that simply saying something to her before going off on the whole MDW stunt probably wouldn't have worked (since then there wouldn't be a story), but the point is that- as far as we're shown- nobody even tries.