I think this principle is very much applicable to the potential election of Donald Trump. If you're looking at a 17 way contest and you only need a plurality, and besides only 13 of the 29 million people in the Republican primary voted for Trump compared to the 126 million who voted in the 2012 presidential election. So it's very much true that for Trump in the primary all publicity is good publicity. But that won't hold for the general election.
I suppose that's why the betting markets are only giving him an 18% shot at winning. That's still a lot and many things could happen between now and the vote but Trump's strengths in the primary ("bad" publicity) aren't a strength in the general election.