Belt stretch

OK Im out to start an argument here. Im flattly stating that stylus drag and the effects of belt stretch on belt drive tt's is pure BS. Unless the motor was grossly underpowered there is no way there are any audible effects (even to a dog) related to belt stretching. Im not saying that there is no measureable speed fluctuation but Im saying that even if you have something sensitive enough to measure it you still cant hear it. So there