I think I could have used that power to weight chart in an argument a while ago. Thanks for putting them together. I don't know why some people have such a negative attitude about them, you can pick apart any set of data if you don't like it.
Arguments like "well they use different engines now than before" No ****, that's kind of the point. Although the cars have gotten heavier/bigger, it seems like some of the manufacturers have been able to keep the same efficiency by using different engine technologies and increasing aerodynamic efficiency.