Alan: Wow! Kudos for the work you've put in to this matter.
However, isn't this part of why pgmusic came up with RealBand?

Mac: In BIAB, G2 (yes, GAD) actually would mean (frustratingly incorrectly) G(add2) (GABD). As far as I'm concerned, there is no such animal as G2; there is either Gsus2 --OR-- G(add2), major or minor.