I don't know, I seem to remember a recent thread about RO 'before or after a softener', and folks mentioned testing lower TDS after the softener. I can't imagine salts fooling a TDS meter but I honestly don't know how they work.
Yep, you're right, says it right in AaronT's write up. Cool, now I'm even more excited to start using it. Old habits die hard though, it's going to take a lot to keep me from dumping ferts in every time I see a spot on a plant.