I’m pretty certain the theory didn’t start with Limbaugh.
As stated by others, Rush isn’t the first, lots of voices on the right have been pointing out some of the relationships and motivations of the players, and drawing some inferences and positing about rational economic interest playing a part in the utterly irrational hype about this non-event.
Despite what the media and leftists would like you to believe, we’re not mindless drones that get our marching orders from a voice in a studio somewhere. If that were the case then by definition we’d be liberals.
It’s usually the other way ‘round, our studio voices get their stories from us and simply preach to the choir. Good business model all around, especially when your delivery is artful enough to prod some indignant wails out of the liberal peanut gallery.