So in other words, we're looking at the wrong mutations (Taq and Bsm) to try to determine our vit. D requirements?
Yes, which is part of the reason why Yasko annoys me so much. There are plenty of SNPs which have the sort of impact she claims, but it's usually not the SNPs which she claims are having it

I've updated the VDR thread to have a bit more explanation of the effect of the SNPs.
That thread was interesting, reassuring, and partly over my head. And it looks like genetics is borrowing terms from my field (linguistics): "missense mutation", I love it! I want it for my username.
Genetics is a lot like reading and translating. On the coding part of genes, each three-letter combination of nucleotides (ACGT) spells out a specific amino acid to be added to the protein which is coded. So if a single nucleotide (letter) changes, it can result in a completely different amino acid (word) being created, and modify or even prematurely end the protein (sentence).
However sometimes the changed letter doesn't have an impact at all, especially if it's the third letter in the three-letter combination of nucleotides. As an example, if the first two letters are "CC", it doesn't matter what the third is, because CCA, CCC, CCG, and CCT (CCU) all create proline.
And of course, inserting or deleting a letter in an exon of a gene can create a HUGE mess, due to every three-letter word then being shifted, and creating a very garbled sentence instead of a nice functional protein. So ...CCC,GCG,AGT,TTG,TGT,ATA,C... would create Proline-Alanine-Serine-Leucine-Cysteine-Isoleucine. But if the first C is not present in the gene, it comes out as CCG,CGA,GTT,TGT,TGA which creates Proline-Arginine-Valine-Cysteine-STOP, which is going to cause very serious problems unless it's happening late in the entire gene/protein/sentence.