there's also the argument that if you're going to run closed loop, you are never going to achieve the wideband AFR, all you'd be doing is making the BLM system work harder and harder to achieve an erroneous goal, so tuning to the trims would make more sense.. even if the AFR isn't great, at least it's consistent.

in other words i would tune to minimize trimming or abandon closed loop and tune OL with your wideband.

as far as PE goes, either method would yeild a reasonably accurate base fueling shape upon which power enrichment can be tuned properly to the wideband target anyway