Why don't we try to resolve this issue on this talk page, rather than going back and forth with edit wars?  I believe a specific age range should be in the lead, and there seems to be more or less a concensus that 1965 is the most used first year.  I don't think there is any ambiguity about this...whether we agree or not (and I don't happen to agree that 1965 is the first year), I don't think there is any question that 1965 is the most widely used beginning yr for X.  Also, Generation Jones is certainly relevant to this.  It's not that Wiki editors have to "face the claim that a Generation Jones exists", as you say.  There is no question that many credible sources do believe that Generation Jones does exist, and especially with its accelerated emergence recently, it should be included in any discussion of the birth years of GenX, since it is directly relevant.