You do realize the single thing stopping double AST parties from being meta is cards not stacking right? If card buffs stacked it would be stupidly broken.

As for you leaving when you see another AST, that seems like you being bad at teamwork. It's not that hard to observe your fellow ASTs card buffs and when they have something up, and if you overlap a tiny bit so what? You don't see double SCH parties complaining, and a lot more than just their buffs overlap.