People are made differently depending on your tendon insertions fiber type etc... You come to lift born with these differences. How are you to say how a bench shirt effects different people.
Is it not possible that some people are built in such a way as to get more out of a bench shirt than the next man, or they could be just more skilled at using it. Fine. Now you have a skill component to the lift as well as a skill component of how to use an external device, and we arent exactly talking a few pounds here.
I understand the injury argument, but adding hundreds of pounds to your lift is another story entirely. I guess that is the way it has to be, the reason it bothers me so much is because there has got to be people out there who cannot win meets merely because of a shirt. There arent sprinters saying, damn those nikes decrease his times by 60%! Or he adds 23 inches to his vertical with his shoes!!
Another question is how much overhead work do most powerlifters do? It is well known that not doing overhead work and just bench pressing is murder on the shoulder, but I guess at the heavier poundages it may not matter. Anyone?