
It definitely does change it -but not necessarily after just the one time, in my experience it is when it has been done a few times. Often it changes the colour as well -spot Blenheim Cavaliers out and about and see how pale some are and they have invariably been clipped. In fact when I worked at a vet's and she specialised in skin problems and many dogs had to be shaved completely, I do remember dogs (in particular Wire Foxterriers) that ended up much lighter in colour than they used to be.
It works the same in cats as well. I am very much against shaving Persians routinely, but some breeders do with their breeding cats that aren't shown. I have done it in a few cats where there has been particular reasons, such as very old age making it kinder than full grooming sessions. After one time, the coat grows back normal. After more clips, the coat will never be the same again and has to be kept clipped as it will be impossible to groom. Cotton wool like, curly etc. Again the colour changes too.
It actually works a similar way in people too -we all know cutting your hair will encourage it to grow and the more you shave your legs, the thicker the hair that grows back will be.