How is it not an assumption, if as in Darwinism
It is not inconceivable that the pseudogene was coopted for some function yet to be discovered...
and in Darwinism there is no "purpose" in the strict sense of the term in the first place?
Cordially,
That wasn't your original claim. Your original claim was "The conclusion of common descent is built into the bare assumption that the lack of the L-gulano-g-lactone oxidase gene is a "defect", or "nonfunctional" version of a gene that was purportedly functional at some point in human history".
The original function of L-GLO isn't purported, and it isn't an assumption. Try to muster just a smidgen of intellectual honesty.