I like skydragonknight's answer.
PsyRef allows the re-picking of a feat / feat-slot , but you can't put anything there, that you couldn't have done in the first place.
Dark Chaos (both) use different language.
iirc - any feat can be re-done into whatever, with it.
1st level Soulknife doesn't have a lot of options, just multiple Hidden Talents via the Mind's Eye update, for retraining or PsyRef;
whatever Azrael is angling toward, could be done with DCFS.