Spain had similar success in the same period, but I think it's obvious Messi was the biggest factor. Pep using him as false 9 changed things, though.
Yes.
Pep's era was a mixture of a lot of "good things"
1. Pep is a 8/10 or 9/10 quality coach
2. Messi is the best player ever and in those days he was young, full of energy, motives and he was hungry for a success, titles and 1000s of Goals. Also his body was much younger and in a better state than currently
3. Other players, mostly Spanish were one of the best in the world, and also in their prime, like Xavi, Iniesta, Puyol
4. Tiki-Taka was new and other teams didn't know how to defend well against it, as they know today
If we took Pep back today, would it be the same Barca? No way.
1. Messi is not that Messi anymore. He was young and hungry back then. He is still the best currently, but he is not as good/as hungry as that Messi.
2. Xavi, Iniesta, Puyol? Their prime is behind them. You could see the difference in motives and hunger between our players, and between Madrid's players yesterday, for example. They haven't won CL in 12. They will die on the field if needed.
Our players, who have won everything will hardly die on the field. More likely, they will walk around..
3. Tiki-Taka in 2008 and Tiki-Taka in 2014? Madrid didn't know back then how to defend against us. Even though we can still win against them, the sad truth is that they are getting closer and closer to us in the last 2-3 Seasons and that they cope much better today against us than in 2008 or 2009.
The same is with other teams like Chelsea, Atletico, Inter, Bayern (when they are NOT playing Tiki-Taka)
I know, people will always say: It is not because they have learned how to play against us, but because WE play/run/press weaker than before..
It was not all about Pep back then. It was a perfect era with a perfect coach, with a perfect Messi and with a bunch of other perfect players for our system in their prime (Xavi, Iniesta).
Imagine Pep in Barca in the next Season. Who will lead our team? 35 year old Xavi? Messi who is walking around on the field? Fabregas? Sergi Roberto?
Imo, people who are giving too much credits only to Pep and who think that he would save us again in 2015, are slightly too romantic.
Football is evolving all the time.
Except us.
We are still living in 2009'
It seems that we will repeat for the next 10 years: "We just need to go back to our roots, to our 2009's system.."
(Even Van Gaal's first era in Barca was extraordinary. When he came back a few years later, he was horrible and he was sacked. Did he lose all his knowledge in those 2-3 years? No, but the times have changed and other teams, especially Madrid have evolved back then)
Sooner we wake up, it will be better for us and for our future.