Any fixed formation is predictable in real life, the best teams rotate player positions - that's why 4-2-3-1 became so popular, with the 3 constantly interchanging (Chelsea on a good day have the best 3 in the PL for that formation)
When Barca were at their best, they changed player positions a lot and Pep was constantly looking for variations. When he left a few of my friends said that whoever got the position would have the easiest job in the world - I argued that it isn't as simple as putting out the 11 best players and winning games
Heynckes' tactical masterclass in the semi-final proved that to be the case