I am not sure it is a myth exactly, but I think it could easily be an oversimplification. As you may remember, I was looking into blade design/manufacturing to try to make sense of some of the honing information. I talked to a custom blade manufacturer and he said that he designs his razors to be honed with one layer of tape. When I asked about the hone and edge wearing over time to keep a constant bevel angle he said he doesn't think that the spine and edge wear evenly enough for that to work.

And my head just started going through all the variables one would have to consider, and all the factors someone would have to control, in order to ensure that were to happen. But my rudimentary brain came up with about five before the words "oh my" escaped my lips.