The claimed HP numbers by tuners also vary by how they compute the powertrain losses.

With AWD there is no set formula and some use 12% while others use 15 or even higher and that would show much different crank readings.

I would prefer they started to show the real reading at the wheels and compare it then to stock numbers read also at the wheels.

No one does that because 550HP does not sound as impressive as 690HP and the majority of readers would not be bothered to learn about "nuances" of that sort.