I think think the reply you got was mostly talking about their marketing. The MSDS is a federally regulated document. The results are derived directly from analysis. There would be real world consequences if the MSDS was incorrect.
MSDS took a bag and tested it, doesn't mean each bag is the same. They can't put an official amount on the bag like MSDS came out and stated, because it's not correct. The same goes for the homegrown bag. They now have 2 different versions out, that the MSDS sheet does not cover. It's wrong either way you look at it, product has calcium, but not straight 4%
