Look, I didn't design it and I'm not professing that I could. These are direct quotes from Colin Pass. I have them written here in front of me. It appears the term "buffer" would have been more correct than "autoformer", but I hardly made it up.
If it's bullshit, I'll eat crow.
My understanding was that the only active portion of Pass' design was a buffer which was externally powered. It was used, in Colin's words, "to couple the input and output impedances". Clearly you've a more thorough knowledge of what this means than me.
I've clearly run afoul of the BS committee, so I'll keep my mouth shut on technical details from here on out. I respect the high S/N on this forum, and have intention of degrading it.