And nobody knows details about calibration of that dyno, could be very low or very high.
What I trying to repeat here is that dynos, especially the normal ones used by open public, show is just a number, not an absolute value and they need to be consistent and only the delta is useful as an absolute value considering before and after values. Dyno is just a tool.
PS: As far as I know the most optimized setup for the less loss are central engine - rear wheel cars with very short axles, Ferrari using one of the finest materials, shortest and most optimized transmissions was around 12-13% loss if I remember correctly an official statement. So Kappas/LS family cars with their long axles, over 10 years old diffs, their pickup trannys would be a dream to have only 17-18%, but that's only my opinion.