Yeah, but the fact that Barcelona is unchanged is more of a problem than a benefit for you. In 2009, Busquets was in his first year with the club and wasn't fully aware of his role... now he's one of the most important players in the team. The team has grown and matured in their understanding of the tactic and each other immensely in the past 2 years. That team only maintained 51% possession in the 2009 Final, and it was much less over the course of the year as well. Further, Carrick is still going to be tasked with shutting down Iniesta, a job he was completely incapable of in 2009 and likely won't be able to do this time either. Messi understands the false 9 role much better now (it was a surprise when used in 2009). It's just a completely different monster, and if Fergie is preparing for this game by breaking down the 2009 tape he's going to get hammered.
SAF has shown to be the most shrewd manager in football, possibly in football history. He knows exactly when to change with the times and all that good stuff. But he's not a brilliant tactician, and he's not the guy who is going to mastermind a plan to beat Barcelona on paper. Obviously his tactical prep will make a huge difference, but he can screw it up easier than he can get it right (for example, going with Giggs and Carrick as holders). If Man U are going to win they're going to need to be hugely motivated, a steel reserve, some moments of inconceivable individual brilliance, AND luck. It can be done, but it's more up to the players unless the manager really cocks up the tactics. I get that you have faith in your team, but also remember that you are rightfully huge underdogs. This is the greatest club side of all time.