The intention behind away goals was to give away teams a slightly advantage when European games were extremely rare and people had little experience of traveling to "foreign" teams. With the homogenization of styles across Europe (think of the amount of teams playing 4-2-3-1 at the moment, for example) it's redundant. Both teams scored three goals and won away from home.
Agree with Tyton about forcing an open encounter, though obviously in this case it hurt to go out.
Interestingly Koscielny seemed to play a lot better with Mertersacker, both were incredibly solid whilst playing a deeper defensive line, and Vermaelen was dropped to the bench despite being fit to play. Considering he's the club captain, I can see drama occurring if he doesn't significantly step it up. Ramsey also bustled the midfield well and looked to be gaining confidence.
A problem is that Wilshere is injured alongside Diaby, so there is no backup in the tank beyond Coquelin and Rosicky, who at 32 isn't in his prime any more. On the upside, Gibbs back in the team was immense and Cazorla seems to add a lot more than Podolski (though I agree he's influential in the middle) on the left with Walcott playing alongside Giroud, as he drifts inside and opens up space for Gibbs to overlap, which he loves doing.
