I was pointing out that IS and higher ISO with lower noise are not perfect substitutes for each other and not that ISO is better than IS. Both have their places.
IS/VR actually does not alter the shutter speed but just compensates for any handshake. In the example I gave earlier, it basically meant that if the focal length is 50mm, then it usually means that the picture needs to be taken at faster than 1/50 if handshake blur is to be avoided. With IS/VR, it can be taken at 1/15 without getting handshake blur in the picture if the hands are not very shaky. This is what is meant by compensate by 2-3 stops by IS/VR and although it mentions shutter speed, it doesn't alter it. However, at 1/15, any subject movement will be captured as motion blur on the picture. If motion blur is to be avoided, then higher ISO with lower noise would be a better alternative in such a situation.