Are Libertarians Pragmatic?

Russ Nelson recently argued that there is no such thing as a "left-libertarian." In so doing, he points to a larger issue:
I think there's a larger issue here. "Liberal" used to mean the philosophy which is called in the US "libertarian", and which is still called "liberal" in some other countries. Since this philosophy generally promotes happiness and distributes power, people who seek power object to it. Since the philosophy is hard to understand and is counter-intuitive, it only takes a little bit of effort to undermine it.
[Emphasis mine] Is a philosophy that is easy to undermine and difficult to understand in the first place a realistic philosophy? Well, self-organizing systems such as this often display emergent properties that are more than the simple sum of their parts. So the people contributing to the system don't necessarily need to understand the system in order for the system to work. However, it is the "easy to undermine" part that causes the major problem...

I find libertarian ideas and concepts interesting and useful, but I can never seem to get rid of the nagging pragmatic objections to it, such as the one outlined above.