Autosense
I think it is worth remembering first and foremost that two of Hoover's key philosophies was to have as many gimmicks as possible, and to offer much confusion as possible in respect of the choices of cleaner available.
In principle, the idea of autosense is that in normal use the motor runs at a wattage sufficient for cleaning carpets. When grit was detected, Hoover decided it would be useful to boost the wattage so as to aid cleaning. Were this not enough, the user had the choice of overriding the autosense feature and running the cleaner at full power.
Now, when autosense was confined solely to the two cleaners in the Turbopower 1000 range, it all made sense, as the 1000 watt motor was higher than that of the 800 watt motor in the Turbopower 2 series. But when autosense was introduced to the Turbopower 2 cleaners, the 800 watt standard motor power dropped right down when using autosense. This is confusing for me. Either the Turbopower 2 cleaners were needing an 800 watt motor, or they weren't. Effectively, if the autosense models were capable of cleaning at below 800 watts (autosense mode) then the standard basic Turbopower 2 cleaner should have had, say, a 600 watt motor, because as it was it very much looked like the basic 800 watt cleaner was a better choice as it was designed to be used at 800 watts all the time, unlike the autosense which potentially ran at three different wattages.
Of the autosense cleaners which came to me for repair, I did note that most of them seemed to arrive with boost button pressed down, suggesting that the user preferred full power all of the time.