While a valid case for your assertion can certainly be made with regard to Hannity and some of the other radio ranters, it is flatly not true for Limbaugh. He does teach people to think, and over his career has brought many people to a better understanding of conservative ideas and the foundational principles upon which this country was founded.
What he understands clearly, however, and what you obviously do not, is that most people can only be "reached" if they are exposed to ideas and information in an entertaining manner and at a speed which is comfortable to them. If they don't enjoy the program, they'll simply tune out.
While you and many others here might prefer a more intellectually concentrated, wonkish and didactic teaching format, the hard reality is that such an approach will never garner sufficient market share to reach very many people. Whatever instruction radio talkers may attempt must be leavened with entertainment.
There is no question conservatives need to re-learn how to think, but that condition is not limited to conservatives. The American people as a whole face the same problem. Most of talk radio certainly doesn't help, but some of it does, including Rush, and your blanket assertion is simply incorrect.
Nope. Rush has a two-hour daily monologue. The only "conservative ideas" you'll get from Rush's show, are Rush's conservative ideas. There's no room for debate or fresh viewpoints in that format.
Nice post!