Yes sorry, Dyno D is "Dyno Dynamics" the manufacturer of the equipment, and a rolling road is a stationary platform - maybe you call them something different in the US?

After a lot of reading I'm convinced the traction wasn't off, can't believe my car - that he said was all fueling good and running fine - would only make 199.8HP at the flywheel when stock should be 215. It has exhaust, filters & map done and is definitely quicker than my girlfriend's stock XF the same.