Rarely is there a media appearance in which Herman Cain doesn't want to drop a reference to "9-9-9," his tax policy proposal made famous when he was seeking the Republican presidential nomination. But while speaking on a panel on MSNBC yesterday, it wasn't an issue he wanted to spend too much time on, according to Politico:

During a [commercial] break, we indicated to Herman Cain, who was on set, that we planned to ask about the Tax Policy Center finding that 9-9-9 would raise taxes on 84 percent of Americans and by nearly 1000 percent on the lowest-bracket earners. He called the numbers an unprintable word and threatened to walk off the set if I asked the questions. He later said he did not come on the show prepared to defend the proposal, which he is still pushing and mentioned several times. He said I should e-mail my numbers to him.

Here's Cain's appearance on "NOW with Alex Wagner":

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