Want to know a great secret of life?
Penis is a balloon. It gets hard from blood pumping it up. If the same size guy has a huge cock it just does NOT get as hard and fun as the same guy with a smaller one.
Not enough blood in the body to give it a good hard one.
Now it is not just one balloon, there are like sausages filled with sponge inside. And you would need to stretch all of them exactly the same way to have a bigger and still straight penis. If they do not stretch evenly your penis gets an odd shape. Stretching the penis skin itself is of little value.
So in response to your answer.... The mechanics of stretching the inner sausage just does not add up. Unless you mean the penis pumps inserted inside. They work amazingly well. Utterly delightful