No one forced Pep to play Cesc over Thiago that is a figment of your imagination.
Pep was one of the main driving forces behind getting Cesc who was better than Thiago when they were both at the club anyway.
The point I'm making with this comparison is that clubs presidents/owners can and definitely will push their influence for certain players to play over other players.
Cesc was always going to come back and he did because of Pep's success, that was the proverbial straw. Pep wanted the Eto'o-Ibra swap but I don't him recall him categorically demanding Cesc. It was a publicity signing from Rosell that Pep was open to, not Pep demanding Cesc. I think this was a prime example of why I think Pep and Rosell never saw eye to eye. Pep had the team playing well enough to force Cesc into the mix but he'd be blind if he didn't realize how much him and Xavi in the same line up caused balance issues with the team. The fact that he kept him in and that other managers did the same, even though it was clear how disruptive it was at times, I think is at least partial evidence of how publicity signings that aren't a direct request of the manager are a reflection of the owner/president and for political reasons, must play over certain players.
Great example of this was the whole Shevchenko drama at Chelsea between Mou and Abramovich. That was the beginning of the end of Mou's first spell at Chelsea.
How you can you really claim the victory over Bayern was 'only down to Messi'?
If you want to see the limits what Messi or any player can do on their own just look at Argentina in the Copa. Messi like every player ever needs a platform to perform and with the signings of Suarez, Neymar etc he has been given that more than ever.
The reason why I say Messi won the tie for us against Bayern virtually single-handedly was the 2nd leg. Bayern showed in that game that they were at least on par with us. That for me is important; if Messi doesn't go super saiyan in that 1st leg and score two goals plus set up Neymar's, that game most likely ends 0-0. Also, we got the benefit of the doubt from the referee in the build up to the 1st goal and we pounced as Bayern slowly reacted to the ref's decision.
I'm not at all saying sell everyone but Messi but I'm highlighting how he inspired in a match when we needed someone to inspire the most, and it's impossible to deny how much his performance impacted the outcome of the tie against Bayern. If we go into the Allianz with a 0-0 or even just a 1-0 or 1-1 tie, it's a massively different game. Messi made it comfortable and put it out of reach, he gave us a decisive advantage.
Every player had their moments last season. Rakitic's goal against City killed that tie, Neymar won the group stage for us in the 2nd leg against PSG with that screamer he hit, Suarez also put them to the sword as well in the quarters. It's just against City, against PSG we were
clearly the better team, even when they were fully fit. That was not the case against a Robbery-less Bayern. That's why Messi's 15 minutes in the 1st leg was so vital. That's why he was the difference, and to bring this full circle, that's why our recent success is 95% on Lucho, his staff, his transfers and the players and 5% on Bartomeu/Rosell.
I give Rosell a measly 1.5% for his transfer of Neymar (even though the costs) and like 3.5% to Bartomeu for helping balance the books and giving Lucho a chance.