Question: is there any evidence or empirical experience that can tell us whether the length of the HSI bar signifies different power requests from the HSD in the different modes? I.e. 3/4 bar in PWR mode, is the same power request as 3/4 bar in ECO mode? That is, is the length of the HSI bar dynamic (depending on the mode used)?
Yes, get into SHM in both ECO and PWR mode, and see if the spot on the HSI bar is the same. It should always be slightly above the midline. If the midline is 50%, SHM is around 60-65%. It only works above 50 mph. If at 55 mph you can get perhaps 70-90 mpg for about 30 seconds. You have to control the SOC, however.
I bet with your plug-in kit On good stretches I like to use SHM at 65 mph getting about 80 mpg. I can hold it for a long time if there's a slight downhill.
I get your point - but that is obviously so - if I keep the gas pedal fixed, and I change the mode, the HSI bar will change it's position because the mapping of the gas pedal is different. I am asking something different. I.e. what does for example a full bar, before PWR, mean in terms of power output in the different modes? the same output level (achieved at different gas pedal positions) or slightly different? because otherwise when you put PWR mode, you fill the bar super quickly and you end up in PWR region immediately, and in ECO you "never" fill the bar.