Thing is, I'm quite sure Flekken has been doing very well lately, seeing as Freiburg are 2nd in the league. The added caveat is that Flekken was sort of "discovered" by Van Gaal. He was the one to first call him up and repeatedly said Flekken is a real "Van Gaal keeper". Pasveer has been in abysmal form lately (actually he just went back to his regular midtable Eredivisie level), but I suppose he will be less anoying whilst sat on the bench as opposed to Cillessen who comes across as a massive tit.
In the end though, it's just keepers and as Johan Cruijff said, if you have the ball, you don't need a goalkeeper. Or something.