When I wrote the previous post and read the comments on it, I finally realized that I actually have enough knowledge to play the KRpKR ending well. I know the boundaries of my knowledge, that is to say I have a clear idea about what I don't know yet, but it takes another 2 weeks to master that. There is no reason at all to flick in that study now.
At the moment I know the technique how to promote a non rook pawn and how to promote a rook pawn. I know how the Lucena, Philidor and Vancura relate.
That's why I started with bishop endgames yesterday. It turns out that I have much more feeling for that endgame allready. I have a clear idea what I'm after, and the amount of techniques are already known. Most of them that is. I score very well at CT, and find those problems much easier to calculate.
So hopefully tomorrow I can move on with knight endgames. I can't wait.