Interesting point of view. AA would be the loser, though: SR is in a terrible position (thin local traffic from a small base, tiny hub (ZRH) with only one runway and geographically locked) and SN isn't in a great one either (talk about a small local market!). The question is whether a BA/DL combination would get the transatlantic immunity that would make such an alliance preferable over the BA/AA one -- and I personally doubt it would.