He is wrong in that for any healthy person any exercise is better when performed over the greatest possible range of motion. Below parallel squats are better than parallel squats which are better than half squats, etc. You just get more muscular development that way. If you stop the bench press above your chest, you're lessening the involvement of your pecs, and making it more of a shoulder and tricep exercise - may as well just do overhead press, then.
That's
for any healthy person. Obviously if someone has a pre-existing medical condition or injury, they may have a restricted range of motion. And obviously not everyone can begin with a full range of motion. I have a client who started at 165kg unfit - I did not have him start with deep squats, he had to work up to it. But assuming a healthy person, the idea that you should deliberately restrict the range of motion is wrong and stupid - just do another exercise instead.
He is correct that the bench press is an exercise which places certain joints at risk of injury. However, the same is true of all exercises. The questions must be,
- the exercise offers risks, what are the benefits?
- given the risks and benefits, is there another exercise which gives the same benefits but less risk?
Exercise carries risks, but doing nothing carries risks, too. Adult onset diabetes, back pain, herniated discs, knee pain, these are all things which come from doing nothing, and are just as painful and disabling as popping a shoulder would be.
As to comparing exercises, we can compare the overhead press and the behind-the-neck press. They offer the same benefits of developing overhead pressing strength and shoulder/tricep development, but the behind-the-neck press offers
more risk.
So, what benefits does bench press offer? What risks? What are some alternative exercises?
That'd be a whole article by itself. It comes down to what you're after. Physical training can change the way you look, feel and perform.
In terms of looks, the bench press gives you shoulder, tricep and pec development. It could be replaced by overhead press and dumbbell flyes, but that's two exercises in place of one, depends if you have time or not.
Feeling, or health - well, it's always good to be stronger, but then there's the risk of injury. The greatest risk with bench press for the typical gym-goer is not really something popping out because they touched their chest with the bar, it's that they'll focus on bench press, and be benching 120kg while unable to squat, row or deadlift even 80kg. This leads to their shoulders rolling forward and turning inward, and a rotator cuff impingement. It also leads to poor shoulder flexibility, so that for example the guy cannot get his hands up to his shoulders to hold the bar in a front or back squat, which I have seen a few times.
In terms of performance, you have to look at what you're training for. If it's just getting overall stronger for everyday life, an overhead press will do as well - not many people need to push something heavy off them while they're lying down, lots of people need to pick something heavy up and put it overhead onto a shelf or truck or whatever.
But some sports will need horizontal pushing strength, for example rugby. And as before, if you're not going to go all the way to the chest, the pecs aren't involved as much, so you should just do overhead presses. But then you'll be in trouble on the field when another player is directly against your chest. And as a sportsperson, the chance of injury in the gym is absolutely dwarfed by the chance of injury on the field.