You can't get full-drive data from the energy app, but you can compare a 30 mile trip to the IC trip app and see that they often don't match.How can I get useful full-drive data from the energy app? It only shows efficiency for last 30 miles. Next drive I will compare the Wh/mi on IC to app. It was similar, I never noticed a discrepancy but I will check. Why would they be different? Which do you think is more accurate? IC should be accurate.
If you average 284Wh/mi in the energy app, you will see that your projected range (average, not instant) will be equal to your current rated range. In my limited experience (~3800 miles) with my LR+, hitting rated range in the energy app reflects a much lower number in the trip app, somewhere in the 250Wh/mi range.
Doing pure unit conversion:
(rated consumption in Wh/mi) * (rated range in mi) = (usable capacity in Wh for the purposes of EPA rating).
Thanks to the units, we must fit this equation. If Tesla is being untruthful about 284Wh/mi, then we will have to back out the true EPA rated consumption. Perhaps that's really what you're trying to do. Because otherwise we have two of the variables and can calculate the third.