The point that is being missed is they were in a salary bind with Harden. They believed that they couldn't afford to sign him to a big contract. They didn't just willy nilly trade him. They didn't want to get rid of harden. They had 3 great young players, and they could only afford to keep 2 - KD and RW.
I seriously doubt they are trading RW, and especially not for a pass-first pg like Rondo. They need RW's scoring badly.