I have gigged at least a half dozen “pre-Gibson” (a mis-nomer) basses and auditioned at least twice that many over the years. The one thing I can say about them is that none of them ever sounded or played the same. The last one, which I should have kept, was a Signature 5; but, it had some kind of one off modification in the Bartolini circuit. When I tried to sort that out with Mike, he explained that he had very little to do with the preamp constructions, had no record of that particular mod, and that Bob Lee would have handled all of that. I ended up with a Mike Pope preamp in that bass, which was far superior for my prefs in all respects.
As noted above, Mike did have a “standard” Bart circuit; but, there were also significant variants; and Bob Lee was handling that end of things. FWIW, my C6 is a Nashville instrument; and it is by far the finest 6 I’ve ever played. Gibson did mishandle their relationship with Mike at the corporate level. But, the staff in the Nashville shop IME were fairly on top of their game. The changes they made in the Bartolini circuit lined up with changes Bartolini were making as they phased out the TCT for a good while.
So, some of the issues were with Gibson, but some of the changes would have been equally happening had Mike retained the brand. Anyhow, it’s all history now. I just think it is inaccurate to villainize Gibson beyond what they actually did wrong.