Please point to where I said 'only'. Dr. Mann's book was published in 1998 so swings he evaluated for the book were not only the 80's as you stated but up to 1998. If you believe golf swings are like car models with a new one every year then I'd like to see your categorizations
You stated that I did not draw the line through the middle of the upper torso
. Given that we were discussing the position of the shoulders I inferred that you equated the position of the upper torso to that of the shoulders. Perhaps this was just a subtle way to attempt to change the definition or context of the discussion. In any case, as stated, I was looking to define the shoulder position because that is what is relevant to 'facing the ball at impact' as taught in SA methods.
As I mentioned elsewhere if you want to talk about the position of the upper torso at impact that should be in a different thread. This thread is about 'facing the ball at impact' which is related to the position of the shoulders and not the position of the upper torso at impact.