1. Probably.
2. No.
In the book it is mentioned that you shrug at the end of the movement, making impingement impossible. Two questions arose for me:
1. Does this mean that not shrugging impinges the shoulders?
2. If so, doesn't the movement at some point impinge the shoulders (before you shrug)?
1. Probably.
2. No.
Look at the drawing in the book. It doesn't impinge on the way up.
I think the logic here is that the downward force from the barbell with your GH joint locked out will cause problems, hence the shrug at lockout?
About two years ago, I had shoulder surgery. The surgeon said that I had a great deal of arthritis and that my shoulder was unlikely to return to normal. However, he gave me the go ahead to slowly start lifting weights. He said I wouldn't know what I could do until I tried. Oddly enough, I have no problems with the shoulder press. The bench press does cause slight pain to that shoulder.
I tried a narrower grip. It did seem to hurt less. Thank you.