Some/most of it is beyond my tech knowledge as well, but I do understand the basics of it.
I've relied upon techs/friends to update my tube gear in the past and I gleaned a tiny bit of understanding from doing so
This would be good info for your local repair person to read/consider.
Until 10 years ago I did not know what the tiny transformers a friend installed on my Dynaco ST70's, being used as mono blocks, were for (power supply chokes).
He performed the modifications in 1979, and said that the stock mono/stereo switch/circuit was a bad joke.
The improvement in sound quality from the mod was not a slight one.