With my team, which has won 3 straight EPL and Champions Leagues, I match prep defensive positioning and drop mentality to either control or standard away, even though my hope is to dominate the game. And even against poor opponents. My three tactics for preparation are Woody's tactic with the 3 different mentalities.
I will change between control and standard based on how attacking the opponent seems to play early in the game; if they're attacking me hard I'll drop to standard. If they're not playing very positively I'll play control. If the game gets past the 60th minute and the result isn't what I'm looking for, I'll start walking up to attacking mentality. I never jump 2 mentalities at once. It's almost a guarantee that all of your highlights will disappear.
This year, throw everything you thought you knew about stats and form out the window. Creating 2 CCC's away from home is a brilliant day, even for a top team, in FM13. A 2-0 win away is a very good result. Even against a mid-table team. The way I see FM13; I'm trying to beat up on you if I'm at home. If I'm away from home, I'm trying to survive your initial assault and slowly exert my will on you. If I play a little more cautiously defensively, eventually my quality WILL win out. If I win 1-0 or 2-0 or 2-1, I don't really care that much. The goal is to win.
Your goal in FM13 should not be to create 10 CCC's and win 4-0 away from home. If that's your goal, you will be upset. To win away from home in FM13 (consistently, over the course of a whole season) I definitely believe you have to play less attacking than you would at home.
The whole reason for this is that in the current match engine, there isn't a ton of things to exploit. It's not that easy to build a tactic that concedes no goals while scoring 4 per game. Away from home, what tends to happen is that your team and the opponent are both playing attacking, fairly risky football. If you have the better team, why would you take more risks with the ball, slinging it around at high tempo all over the pitch, when your opponent is playing a high tempo, more pressing style? If you're the better team you're simply wasting possession by playing attacking. If you're an average team then it's even worse, because your team isn't good enough to play attacking football; especially against a team with a mental advantage from playing at home. Playing too attacking away from home, both teams are pressed high into the middle of the pitch and you just exchange possession in non-dangerous areas, and most likely because of the home advantage your opponent will break through.
If you drop a little deeper though, and play just a little more cautiously, suddenly the midfield isn't so crowded and your quality for creating space can come out. Your opponent (as in the players on the pitch) may get frustrated because they're playing at home and not creating chances. Suddenly players are out of position, pushed far forward, and your players have tons of space to play in. This, in my opinion, is why over the course of the season, I have seen more consistent results dropping to a lower mentality away from home.
Have a read through the thread I posted earlier, linking to Loversleaper's tactic thread over at SI forums.
Hope this helps some people, if you're frustrated by seemingly random away results, give it a try; defensive positioning + lower mentality away from home. Don't just do it for one game or 15 minutes and get frustrated. FM13 requires patience; you're trying to be the best team over the course of 8-9 months, not 2 weeks.