X-Factor #72-#73 is a bit more like it. It's a twist on a murder mystery with the main question not being the identity of the killer, but the victim. Madrox was shot dead at the end of the last issue, but then... turns up alive. It was a dupe, you see. Coming at this from 2014 and with my background my immediate question is "is there even an original?" This is the first dupe that has died, apparently. The surviving Madrox was expecting to be able to reabsorb it, but finds he is unable to. The patch-and-merge problem is not possible to solve with a corpse, and so he finds an entire set of memories gone. Including the identity of the murderer, presumably.
But then another Madrox turns up, also claiming to be the original. He says he pre-dates the events of the Muir Island Saga. This one is at least partly co-original, if more unofficial; they can (to the X-Factor Madrox's surprise) both create dupes. We never get quite to the point that they realise there isn't a difference between them, other than the path they take, I am sure that will come.
#73 touches on a social issue that hasn't really been covered by X-Men comics before: the issue of preferred nomenclature. We've had a few terms thrown around as abuse before, such as "mutie" and "genejoke", but "mutant" itself has been treated as a neutral term. But such terms tend towards the abusive. "Mutant", like "homosexual", has a more than a whiff of clinicalism around it, too. You would expect mutants as a group to come up with some term of their own, that they'd try to promote.
This is not what happens in #73. Guido is a bit annoyed with his television interviewer, and so makes up out of whole cloth the idea that "mutant" is considered deprecated by mutants and that the term "genetically challenged" is considered better. One problem is: he really did pull that term right out of his ass. Other mutants are puzzled and push back against him. The other problem is that, although this is modelled on "physically challenged", the majority of new coinages of the form "[something]ly challenged" terms are either gags or imagined usages. Folically challenged, vertically challenged, the list goes on. It is hard to read this as anything other than a joke against people campaigning for a right to their own identity.