Just got my 50mm f/1.2L yesterday, sent it in to the Canon Service Centre today.
Mounted lens on body, with hood (not reversed) on it, and put it in the bag, when I took it out, the name ring had seperated slightly on one side from the red L ring, which caused the focus ring was wobbly. I think it might have been the pressure while in the bag (it was pretty snug inside). Lens elements were unharmed.
Technician told me the name ring or something plastic had cracked on the inside, which caused it to get seperated. Most probably due to too much pressure on the hood which acted as a lever on the lens.
Just a fair warning to not put lens hood on lenses which will be in tightly packed bags 

