We called Maggys switch the "brownilator" switch. IIRC
TAC came later in the early solid state years. Everybody had a
auto color switch & plugged it. I dont think any did any good,
I always watched with it off. Old TV Nut summed it up well.
IMHO the only "auto color" that worked was VIR. Used first in
top line GE's ( of all people ! ) then Panasonic had some.
https://ieeexplore.ieee.org/document/4043073
Maggy gets credit for one huge step, the intro of comb filters.
When that came out people would ask "why is that so much better
picture ?" It stepped most up to the top of line sets easily where
we had a better margin.
73 Zeno
LFOD !