OUR VE TABLES HAVE CRAPPY RESOLUTION, especially over 100kpa
VE stuff is the failsafe/limp backup of the MAF failure, the MAF/rpm = load being a better measurement of fueling than map/rpm=load
VE/SD works quite well with the known VE of the engine, its just not that good at low flow conditions where the MAF sensor gives direct mass measurements of the air, and thus direct accurate fuel can be sprayed.
I tune VE with no PE enabled and get it drivable for when/if the maf fails, MAF/FTC tuning is quite a bit better for drivability
