Seems a lil weird that you'd need to retune efi for different weather as I don't need to do it n/a. But race cars are supposed to be tuned for each track right
AFR should still be pretty much the same whether boosted or n/a.
There are guys running blow thru carbs that don't need to retune much at all. Tell me a carb isn't tuffer to tune, even w/ wideband o2 sensor, after using a computer to see and adjust all your parameters.