You convert to TC for purposes of figuring out what to bet (and how to play your hand in some instances). You need to revert to the RC to add/subtract when new cards come out. Yes, that means doing the conversion at least once a hand.
Think about the math if you did it the other way. Not very pretty. If you don't know why the math works out this way, I'd say stick with KO until you do.
Good luck,
RC