Well, its going to make a huge difference if you don't use lye, and went salt only. Really the only thing that is going to prevent you from extracting the mescaline is the pH, not the ionic strength.

I'm just trying to understand what your saying.... We should test the salt tek without lye, since the lye, being extremely ionic already, makes it obsolete?

If you wanted to of course, just for experimentation. A better idea would be to take freebase mescaline, and test its solubility in both de-ionized water, and salt saturated water. But, i don't see how this would tell us anything we don't already know.