Interesting find Mike.
I'm trying to clarify whether there is a degree of misinformation here. From the end user's perspective they want the best return on investment and to that end I would have thought south facing and pitched to suit the latitude was the most efficient. I can see how moving the panels to generate more power later in the day may help meet peak demand, but if the output / return from the panels is reduced then that won't suit the end user without some differentiating commercial incentive. At the extreme if the panels were off grid with battery storage, then what alignment would you choose? With the development in automotive batteries I know which I would opt for.
The following applies to the UK...
http://www.bio-linknetworking.co.uk/assets/documents/pitch-graph.jpg