Firstly an apology - my post should have said 'detent' reverse' not 'max' for 'slippery' and 'with or without reverse' for 'normal' surfaces. This is from the QRP.
I have always taken that to mean Detent 2, ie around 70% N1.
Alf - the slides are lovely, but not much help in the air. I assume, Jambo, that you now have to carry and use the 'certified' tables rather than the QRP? As you say, you will be having 'fun' this winter.