Well IMO the reasoning is that your fuel system (if not returnless) should be pretty damn linear outside of very low loads, so any issues you have with fueling are NOT fueling related, they are MAF etc. related.
If you DO have non-linear fueling, your hardware is broken, or you have a returnless system.
By fixing things in FKKVS you are hiding calibration problems in load calculation, etc..
If you fix it in KFLF and MLHFM (assuming your fuel system is working properly), as a side benefit you've got your non-fuel related calibration right.
Thanks for declaring that.. I have been lying sleepless at night thinking exact about that! My FKKVS table is now 1.001 because im almost certain that my fuelsystem is linear now with return line and a Bosch 4bar FPR.
Now im a bit uncertain when KFLF is the table to adjust and when MLHFM is the table to corrent... What is it that points me to use KFLF or when to use MLHFM? My understanding is that KFLF is a correction table under part load and MLHFM is due to modified air intak that is so modified from stock that it need a touch up. Like me going from a NA engine to an turbo.. Now the air must pass trough various pipes and an intecooler and so on.. What is a good method of dialing in the MLHFM and the go over to KFLF?
When I think after now.. I should have calibraed mt MLHFM when the engine was almost stock. Then i would have seen the deviation clearly.. I should have modified the car one step at the time derriving from stock calibrated engine.