[the emmitt]

I think the tips for playing a tiny stack (i.e. M of 4 or less in Harrington's language) are useful. I still see people making their emergency pushes with hands that are liable to be dominated by the distribution of hands that will call them, whereas the Kill Phil table at least advocates pushing suited connectors, etc.

However, I certainly wouldn't want to base my whole game around the book for the reasons that have already been elaborated by other posters.