A roll of coins, or any other heavy object, will significantly increase your punching power. Short of ninjas or mma fighters, the average person doesnt have the twitch ability to throw a significant punch. By adding mass, you increase power without needing the speed. Hands are very light. Even a small mass increase will make a big difference.
Yup. In fact, while boxing gloves are ostensibly for the protection of the fighters hands, the increased mass (approx 10oz for heaver weight classes) significantly ups the chance of a concussive strike and/or knockout.
So... it is kind of a mixed bag in terms of if they actually make fights safer.
Learning how to throw a punch isn't that much work and gives you a huge multiple on power output.
Also throwing a bare knuckle punch against someone's head has a large likelihood of the puncher breaking multiple bones, though depending on the outcome that may be preferable to other alternatives.
Nice, this knowledge will help me grab my keys in some self defense scenario. Will practice on sporting bag to avoid injury and verify force increase.
Well, you're right about ninjas. They have Real Ultimate Power, this website told me so: https://realultimatepower.net/ (Don't click unless you're ready to get pumped!)