it fixes some stupid/retarded "feature" gm decided to put in most of the NA tunes.
Basically 2 seconds into pe enrichment you get what can only be best described as a injector pulse freeze. You can't log it make the change to the PW, but you will see the car momentarily go leaner than commanded, before it richens up again.
On a NA car you wont feel it too much, but on a boosted car if your still running closed loop & pe enrichment you will feel it depending on your enrichment strategy.
That makes sense now, thanks Tre-Cool..... Interesting that even 10+ years later finding out there is still more features in the e38