the SOC calculations/display would also have to be incorrect
Perhaps that is possible - Bjorn did say that he would have preferred to run the battery down lower to have a more "overall" test. But the recent coches.net test of several EVs side-by-side, in Spain, ran them down to zero, and that has similar poor efficiency on the Jag.
If the efficiency is rubbish, and nothing that Jag can do about it, they would have known ... surely??
not sure what's up with that number... maybe road conditions)
There was some damp ... no wet though. I think Bjorn said it was pretty flat (almost no regen), and no wind, 20" wheels. It would be fairly cool in Norway now (test was at night too), so perhaps 10C or a bit less. Thus no significant mitigating circumstances that I can think of. Supposedly Jag has more efficient motors (than Model-S/X) too, and CD not quite so good.
Tesla have improved 0-60 via software update. I presume because they found that the components used had better tolerance than original "conservative" settings.
Could Efficiency similarly be fixed in software? Perhaps some initial "development mode" stuff that is robbing power, or doing things in a non-optimal way? Or is "efficiency", as distinct from "performance", something that would be very hard to imagine could be fixed in software?