it's probably easier to understand "cuya" 06:00 Jun 21, 2010
if you replace it with "su" (y que no parece tener su base común -- "su" referring back to "lista"). I think the writer means that the list which X starts with does have the merit of having a "base común" (the items in the list share some common features), even though it is "heterogeneous"; but, in contrast, the list s/he ends up with, similarly heterogeneous, is "worse" than the original one because it lacks that merit that the items in the list "share some common features". This is the author's explanation of why X does not arrive at the desired "set de principios o reglas para la sound argumentation".
Probably the author would have preferred to write "de aquella" instead of "cuya" (y que no parece tener la base común de aquella (lista)), but s/he could not do so because s/he has just used "aquella". | 
The translation workplace 
peer agreement (net): +1
