He's the only one surprised...!!!!!
He isn't though. Of course he knows it isn't optimal. He's just taking calculated gambles to get everyone on the pitch. He puts teams out on the pitch that he thinks he'll maybe get away with all the time, for various reasons - fitness, trying to keep players motivated and happy etc.
If we, us no nowt layman fans, can predict it'll be slow and testing to watch before the game, I can guarantee you Pep knows too. He'll expect it to go like this but hope we have enough to get by, and if not, call in the cavalry. It's his job to do this and make the big calls and 9 times out of 10 we get the result we want so he won't be arsed.