The non-initiation of force idea is the single core, ideal and principle of libertarianism. It is in the details of its practical application that you notice the disagreements between the Catos and Rockwells.
Is there a single uniting principle of conservatism, other than to "conserve" something? Does it matter what is being "conserved"? If not, then I would say it is not libertarians who are over-diversified.
Over-diversification, therefore, makes libertarianism weak in its ability to gain any headway in its success of seating its members in seats of Congress, which is the point of any political party and its philosophy.
"Libertarianism" is not the same thing as "the Libertarian Party". The article was not discussing the goals of a political party.
If "libertarianism" is not the "Libertarian Party," then you have just added gasoline to the fire of its non-definition.
Again, what is it?