I have a few issues with how this works (not sure if bugs or intentional):
1) I have 1 attribute point and 9 ability points still to spend on my primary character. If I select to gain 1 attribute point in a trade for 1 ability point (as per the dialogue) I now have 2 ability points to spend and 4 attribute points. So I lost 5 attribute points, not 1.
2) On my secondary character I have 0 attribute points and 15 ability points. If I take the same trade it's now 1 and 10.
3) The redistribution option is practically useless. I'm level 17, I have lots of skills including from hard to find skill books. I lose all of those skills if I respec. Surely this could be handled better? There's no reason why learned skills should be lost if you respec a character back to a level that makes those skills available. To me it would make more sense as an extension of the level up progress: allow you to subtract back into the pool and it will only register as complete (and trigger loss of skills) when you finalise. Alternatively say that I want to pass on my knowledge to future generations and written down everything I know (then put skill books in my inventory).
I couldn't test adding attribute points in exchange to talents as I had none spare on my two mains.