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No problem. I am just trying to rationalise to myself how these lenses create images like Rays first one. The practical implication is that the longer lenses make it possible to get the whole subject in focus, while the whole background is dreamy-blurred. If you shoot with the 50 f1.2, you can get plenty of background blur, but it is challenging to get the whole subject in focus wide open, i.e. the working DOF at a given magnification is reduced on shorter lenses (for an equivalent amount of background blur).
I completely agree with you., and this brings me back to my thought process to use a longer lens for portraits, as you have both nice working distance as well as nice blown out bg.
So if I were to choose a shorter telephoto such as 85mm or the 105mm, I like to determine the distance between the subject and the background before choosing a focal length.