This is a discussion between an autism doctor and Cutler about the hair test rules for her many autistic patients. Below the doctor's comments is an early version of the rules. He explains some of the theory behind them. http://onibasu.com/archives/am/2200.html
That doctor reported impressive results with her autistic patients when they used something similar to the Cutler chelation protocol. Elsewhere she also reported great improvement in her own autistic son. http://www.healing-arts.org/children/holmes.htm#results
We hear good results from adults who use it, including MS patients, but it takes much longer--often several years for those with a long list of Hg symptoms.
Basically the hair test is indicating the *effects* of Hg on the movement of essential elements across cell membranes. Hg affects cell membranes.