Fergie's approach during his last years, post Ronaldo, was idiosyncratic in many ways. We often started two traditional wingers AND two highly offensive, "modern" fullbacks. This could be deadly as a counter attacking set-up but it often made us look very stale and rigid when we had to create something from nothing ourselves. If you look at the method we often resorted to in isolation - push the ball wide and get a cross in - we could, in fact, have benefited from fielding some kind of target man in the box.
But you can't look at it in isolation, because the whole team wasn't actually set up to control a match throughout, creating from scratch most of the time, etc. It was set up to punish the opponent on the counter - requiring speed and a bit of flair, rather than some Lambert style big man up front.
Anyway, the key term as far as Fergie's system goes would be idiosyncratic. It worked for him, at least it worked most of the time and to a sufficient degree for us to win the league twice in his last three seasons. But it's not a system I would attempt to copy. I don't think Moyes wants to do that either, not long-term. He has in a sense fallen back on Fergie's approach for the toughest of our fixtures so far - and he has been shown the limitations of this approach as well, not least on Sunday. I think he will attempt to use the players we have differently. His version of United will end up looking more like the team we fielded against Leverkusen than the one he chose again City.