I dropped the '126EF Min Transient Fuel Mass' down from 4.0mg to 3.0mg and the injector floor dropped from 1.24ms to 0.92ms, thanks @kur4o.

Looks like I need to completely rework the low MAP area of my VE table because it's too lean in the instances the pw drops to 0.92ms (bit of a shelf there from before I found the bpw floor). I'm gonna drop 126EF a little more to widen the tuning margin and leave the min pulsewidths set at 0.75ms.

On a related note, has anyone figured out if there's a gain table for transient fueling? I've played with 1240A in the past when the car was NA with a MAF, but I was under the impression that it's entirely ignored in SD mode. I also see the mystery parameter 126ED.