No, you're absolutely right, RC. I was reaching, trying to play devil's advocate, when what we need is clarity and pragmatic guidance. Chalk just shouldn't be there at all, perpetuating a misguided belief. It's in all the calculators and books, unfortunately. It's not that the numbers are fundamentally wrong, but the inferences their inclusion encourages make this a tremendous disservice to the user. The numbers describe a real theoretical potential, just one that can never be realized in this universe as constituted. And the caveats given, by Martin and others, should be more direct. They tend to describe chalk as "difficult" to dissolve. Like I find it "difficult" to levitate my car like a Jedi. This would make an excellent topic for an article on the AHA website or Zymurgy. It would be a very short article, but invaluable.