Yeah, but providing all that info to the uninformed consumer opens them up to all sorts of complaints or worse- "you said I would get 58mpg at 40mph on a 4%downgrade- I don't and I'm calling my lawyer."

Its basic safety-of-flight stuff for (highly trained) pilots but, for the most part, extraneous for all but the most serious drivers. Too much information without training or knowledge of how to properly use it in context is often worse than simple ignorance.

That's not to say it shouldn't be available- upon request, or via ownerslink or something like that?