BZ, you of course make some valid points regarding F1, and the restrictions on development. I suppose my take on it was that of McLaren as a builder, and competitor. I could see absolutely McLaren building the cars, and a outside contractor overseeing the racing. As in the William-BMW association (didn't Williams build the cars but Schnitzer run the show?).
And Lorry brings up a great point, the Honda Indycar engine would be perfect for endurance racing, as was the Porsche Indycar engine of the early eighties that became the backbone of the 936/81, 956, 962 series.
Fax