He's talking about stated range though.. not milage.. mpg.. or efficiency. What he is saying is this:
We take the most popular electric cars, fully charge them, and then drive them at 70 mph to find out just how far they will go. Which one goes the furthest?
insideevs.com
If Tesla was more honest about the real-world range of their vehicles, then maybe they wouldn't sell as many. And he's right. You look at the first question pretty much everyone has after buying their first Tesla.. is something along the lines of my car says its supposed to go 330 miles before charging.. and I just drove about 200 miles and the battery is already down to 10%.
Call it whatever you want. But Tesla's seem to have the most optimistic EPA range of any EV sold today. That "real world" range test points this out as every Tesla led the entire EV field with the biggest negative difference between EPA & actual results. Meanwhile, Porsche on the other hand was the exact opposite, the range on those vehicles is grossly underestimated by the EPA and they can go a lot further than the car's computer & EPA sticker actually says.