I agree that Harley tests can't hurt. I would definitely prefer a Harley if I were to jet off with my wife on a month-long western tour of the USA versus using my 599cc Triumph, even if I feel quite the opposite about general use: a smaller, more nimble bike is superior to a Harley for commuting, weekend rides, and track days.
I think XR750 inspired Sportsters could compare well with Monsters and other nekkid bikes for general use. I got absolutely smoked by one back in '99 up on Skyline. The guy was hauling.
Also, Buell tests could be used as platforms from which to broadcast our appeals to HD for a new Buell engine made specifically to match the engineering excellence of their chassis. If HD took the risk to create the V-rod engine, why not create a new engine purpose built for Buells?