With all due respect, and I really mean that in a positive way as
@2 Sweet is a long-time positive contributor with many insightful posts, but this statement is completely wrong, IMO. I enjoy the truck races, but that is racing dumbed down to the junior varsity level. And it is very much a product of aero taking over. Nascar trucks have drag like a barn door and very high downforce, combined with low power. A formula like that for racing at the highest level would be completely bland and unsatisfactory.
Cup racing is big-time racing. It ain't supposed to be easy. It is supposed to be a contest of skill that separates the contenders from the pretenders. And that requires a serious amount of off-throttle time and braking. It requires the drivers to work hard to get back on the gas early and get drive off the corners. It requires a real speed differential between mid-corner and straightaway... which the trucks don't have. I am a strong supporter of Nascar's move in recent years to put the race back in the hands of the drivers at the cup level.