Take your first shot from a secure rest IE lead sled. Then without moving your rifle from it's original position. Adjust your scope cross hairs to the bullet hole of your first shot. You can take a third shot to fine tune your rifle. That is the theory.

I'm glad that Carl mentioned the fact that this is a theory. If it actually worked, it would be a one-shot system.
Fire one shot, make the adjustment, and without confirming that it took, pack up and go home.
In reality, the confirming shot will tell you that there is a second bullet hole on the target, requiring another adjustment. One more confirming shot will tell you that there is a third bullet hole in the target, requiring still another adjustment, and so ad infinitum.
As the barrel heats up, you will find yourself chasing bullet holes all over the place. Humbug!