Fake lecturer more credible

/The people behind this spoof were John E. Ware, Donald H. Naftulin and Frank A. Donnelly, who wanted to use this demonstration to spark a discussion on the content of the further education programme./ http://www.madsciencebook.com/05drfox.htm

In how many different fields could an actor outperform the real thing? What characterizes such fields?
Is it necessarily a bad thing?