This afternoon I adjusted the fuel pressure with the engine running from 38 psi to 55 psi. Almost immediately. I observed that the AFR at idle dropped from 14:1 to 12.7:1. On the VE table, I had to adjust the cell values in the idle region from 35 to 29 in order to bring the AFR back to my 14:1 target.
Next, I took the car out for a testing run with TunerStudio running "Tune Analyze Live" (auto tune). I drove the car north out of Milpitas on I-680 running in 4 gear and accelerating up to near 5000 rpm whenever traffic would permit until I got to the top of the Sunol grade where I burned the auto tune changes to the ECU, saved the changes to the tune file, shut down my laptop and drove back down the hill and home.
Here is a close up of the VE table difference report: the left table is 55 psi fuel pressure and the right table is 38 psi fuel pressure (blue numbers on the right table are values that decreased, black values did not change as I was mostly running 3000-5000 rpm with 10-30 % TPS load).
The changes to the VE table cell values to achieve the same target AFR after the fuel pressure increase are significant, there are deltas of 10 or more.
Next stop on this journey is to the dyno shop. I have already paid the reservation deposit and am waiting for an appointment date / time.