What they said!!!!!!!!!!!!!!!!!!
Pinch collars do NOT pinch the way you feel someone pinching you. Common mistake to jump to that conclusion due to the name of the collar.
Take a prong collar, put it around your leg, arm, or even your neck and tighten up on it - the 'pinching' action is distributed over a large area, and you only feel an tightening (do it! Tons of people do it, and realize that the collar is not evil).
It isn't just two prongs pinching one spot like when a person takes two fingers and pinches skin, it IS more like what is being described as taking someone by the arm to get their attention - when you grab someone by the arm, your are using your whole hand and wrapping it around the whole arm, and tightening your grip so the person feels it.
If the person is really riled up and in a high state of exitement with the adrenaline flowing, just grabbing them by the arm may not even register to them, so you have to tighten your grip (like a pinch collar), and if the person is really histerical, you need to REALLY tighten your grip, and even give that person a gook jerk or shake to get their attention - you are not hurting the person, but using an appropriately strong physical interaction to get their attention. That is what the pinch collar is designed to do.
This is another issue (use of a pinch collar) that people base their opinion on false information and opinions heard or read - not on actual experimenting and use of the equipment.