For Psionics, does the Expanded Knowledge feat allow you to exceed the number of 'Powers Known' listed for the class? (I.E. have 37 powers at level 20, 36 from max class and +1 from the feat.) The rules are quite vague here from EPH.
Also, is it possible to unlearn a power other than using Apopsi on yourself (Which I'm unsure can even target the caster), in order to learn new powers? Apopsi deletes a random number of random powers of a specified level from the subject, and as far as I can tell you don't get to replace them with anything (Possibly after leveling again? The rules don't say...).