Economics was pretty much ruined somewhere in the ninteenth century by the decision to bring it to academia (which was the first time economists recieved wages I believe). And how it has developed (into the math formula based nightmare it is today) is fairly apparent to anyone who has had the displeasure of being in any economic course. From my experience, I believe academia is far worse than popular literature on economics -- though both are written by economists, usually. Though economists can generally be more enjoyable in rational debate (you don't have to argue against out and out socialism with virtually anyone anymore, for instance).
Also, I think you have to be sure to separate market anarchism from the classical liberals who have existed for hundreds of years. And free trade and property rights talk with the logical conclusion of market anarchism. It is not surprising that classical liberals were rejected and free trade/property rights were rejected. If they believe them for wrong reasons as Adam Smith and maybe even John Locke did. They weren't teaching good ideas, but bad ones. Even Hayek made a huge mistake of taking some seemingly correct ideas and giving into the demands of the statists... by working with their own flawed terms instead of working from actual truth. Milton Friedman had hardly any good ideas and the way he explained them were often times correct and often times leaving huge holes open for the statists to exploit -- it is not surprising he worked with Nixon. It wasn't beneath his dignity or removed from his own principles. If he thought the EPA, controlling the money supply, and giving people negative income taxes (except those that need their money to be with-held) were legitimate government functions, I don't see how he really thought much that was done by the Republicans was bad. It wasn't that he was working within the system that was bad, it was that he had no interest in anything but the system existing.
I believe the development of free market ideas themselves have become more consistent and much more radical with time. It's not only the methods that have changed. Which is important as I don't believe any really intelligent conscious free market anarchists existed until about fifty or less years ago (at least to my knowledge). I don't think free market anarchists have been trying to get through for hundreds of years. They simply did not exist whatsoever in order to do so. Mises is a huge improvement over anything before him by leaps and bounds. And I think Mises did several things that were outside of economics to make exchange and psychology and logic, etc. an irreducible subject matter in the form of praxeology. Which I think is invaluable to the goal of establishing that our position is not one of preference or desired effect (or worse: class interest), but really a part of human nature, the extension of rational investigation, and so forth. And obviously Rothbard is an improvement over Mises (to the position of anarchism). I do not know if Rothbard figured that his teaching post at University of Las Vegas would bring anarchist revolution. If he did, indeed, then he would be wrong. But his written work is invaluable for two reasons: it is radical enough for those who intuitively love liberty and it is readable/enjoyable enough to keep laymen out of academia and still understand great economic and philosophical truths.
Though, maybe you mean the average writer at mises.org and lewrockwell.com that harps on fed-induced business cycles, minimum wage, and price theory, etc. Which I agree is ineffective (even if they may agree with the bigger picture and are ineffective).
As a side note
I would like to know what you think about Austrianism as 'deductive' or a priori vs. what you say economics is: as a demonstratable or in need of proof. I don't understand how one can prove economics in the scientific sense. Mises stated rightfully I think that economic causal factors cannot be disentangled. For instance, someone could say that Canada's socialist system is what allows their wonderful wealth which would then allow new technologies like podcasting. And then if podcasts were nationalized, it would be a dilemma. Noam Chomsky is still certain that computers were created by government and could not possibly have existed in a free market (which would be so "full of hate it wouldn't be worth living in"). Though, I agree with you that is of important to prove ethical theories and philosophy.