In this case, "ATs" stand for Advanced Techniques (e.g. wavedashing, L-cancelling, Ledge teching, etc.)
And Skyler, please do us all a favor and stop judging everyone who likes Melee better than Brawl as someone that's all "NOOO IT SUCKS 'CAUSE THERE'S NO WAVEDASH!!" A good chunk of us that like Melee better than Brawl just like it because we have more fun with it. Brawl is still a pretty awesome game, but for a lot of us with a competitive mindset, Brawl just lacks what Melee had.
Brawl has a lot of problems compeitively. Not really the 'lack' of advanced techs, but more of the fact that there's a lot of really stupid, broken bull**** that's very, VERY easy to do. Dedede's chaingrab is a good example. It can infinitely chaingrab almost any character all the way across the stage so long as the player doesn't do something stupid and mess it up (which isn't often), and sometimes it can even lead to a loss of the opponent's stock, and all Dedede has to do is grab, dthrow, run forward, grab again, repeat. Another example is that if Pikachu grabs a Fox at lower percents, he can chaingrab Fox just by grabbing, d-throwing, and grabbing again without even moving at all, and Fox can't do absolutely anything until about 60-70%, where by that time the Pikachu can just USmash -> Thunder.
Another problem Brawl has for competitive gameplay is tripping. Don't you dare tell me you like tripping, because that's a ****ing lie, and if it's not then you're just thick in the head. It's not fun at all to random lose control of your character for X number of frames.
There's more where that came from, too.
And please don't use the "Who care's if it's slow, it's a new physics engine!?" bull**** excuse. That's like people LIKING the new slower Sonic games and making the excuse "It's just a new game!" Something being new is no excuse for it being worse in aspects that the previous titles had done better.
Also, please don't claim that all advanced techniques were glitches. They were merely exploits of what the physics engine allowed us to do in the game. So we can air dodge in whatever direction we want to? And if we airdodge into the ground at that angle we will slide? Oh, okay, let's use it. That's basically all it was =P The only reason we can't wavedash now is because of the new physics engine not allowing directional air-dodging.
Anyway, I'm done with what I had to say. I don't care to get into some stupid "OMGWAVEDASHINGISAGLITCH" debate here.. not in the Gay Smashers thread where that has no real place.
On a side note, Darkfur is now here in GA with me D: And when he goes home, he's gonna kidnap me and throw me in some random room with an Angelfox... Hopefully he leaves me some catnip, a ball of yarn, and perhaps a scratching post... this cat might want those if he's to stay there.
(If, for some reason you didn't understand that, Dark's now here in my state, and when he goes back, I'm going back with him to live with him, his boyfriend, and my boyfriend.)