He said the first few inches of ROM are particularly hard on the shoulders... he mentioned tendons, may have mentioned something else. This guy has squatted 225kg and at a light bodyweight and I believe competed/coached in QLD weightlifting. Those Oly lifters I guess have a bias towards push press.
But after doing flat/incline bench the other day and loading up the bar for some military, I really noticed it being more stressful just until I got the bar to chin/nose level, at which point the stress subsided a lot.