Creationists have always claimed that isochrons represent “mixing lines” (i.e., straight lines that yield geologically meaningless ages). However, concordance between different isochron dating systems is a good argument against this interpretation. On the other hand, Paul Giem disputed this assertion. He developed a mathematical model which supposedly outlines a possibility how matching isochron dates can be obtained through mixing. He added:

As far as I know, one cannot find this derivation in textbooks, and so those with the proper competence are urged to follow the math closely looking for errors.

But math is simply beyond me. Is there anyone who can spot some basic errors in his derivations?