i'm really not getting this

as i understand the S8, as in most other 'aftermarket' ECU's, you have a 'map' (a table) of load vs. engine speed and the fuel injector duration (or some function of it).

to reduce the fuel input and hence increase the AFR at any particular load and speed, for example idle speed and no load (i.e. vacuum of 15 in.Hg or whatever it is) you just reduce the injector duration at that point in the map. this in no way effects any other values in the map.

so how you set up the fuelling off boost bears no relation to the felling on boost, hence you can run lambda = 1 at idle and cruising at low to mid engine speed and <1 on boost.

have i got it wrong, or are you not fully competent in either using an aftermarket ecu or can't explain it very well?