It could have been added by someone who knew Limbaugh's story was false. I, for my part, am still not convinced that the story is false. I say we wait and see.
Don't the postings by the later posters claiming the story is false serve the same purpose an original disclaimer would have done?
And, if this story by Limbaugh is indeed false, then it was likely to deceive people. The discussion here makes that less likely at least for FReepers.
I detect here an atmosphere that more and more wants to shut down discussion and close our eyes to unpleasant facts. (Even if Limbaugh's article is false, it remains a fact that he published it. In fact, I believe it remains up on his site.)