As they say, all is fair in love and airfares, that said I would say that it's a trick which should be used infrequently, and only if you are 100% certain you know what you're getting yourself into.
As the writer says all it takes is a single travel disruption, and all of a sudden you end up in a place you don't want to be, with no recourse.
Finally could someone who is familiar with the US legal system explain to me how advertising hidden city tickets is a "first amendment issue" in any shape manner or form. The first amendment simply guarantees that the US gov't is not allowed to bring in laws which could limit what you can say and the US gov't is not allowed to take you to court if they don't like what you are saying. It does not protect you against being held liable by private persons / companies if they don't like what you've been saying, especially if you've agreed you'd stop saying it.