Giuseppe Ettorre uses the pinky in thumb position some times. He talks about the pinky high up in his Thomas Martin youtube lessons.
At the octave is to low for the pinky but it is an option at the end of the board.
Imho saying the pinky up high is an absolute ‘no-no’ is old fashioned thinking.
Many are using the thumb in lower positions these days too.
Correct one should always explore the possibilities. I hardly ever use my pinky in thumb position but I am sure there could be uses for it. If it makes you play things that are otherwise impossible to play I would say go for it.
Do you have a link with the exact timing of the video where he talks about this? Interesting.
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