I learned this probably 25 years ago. I'm sure there are probably other videos showing the same thing, but I've never searched for them since I know how to wrap my cords. This technique was taught to me by an older gentleman in Sligo, Pa area. Sadly, I don't remember his name, so I can't give him props.
Heck, I don't even know the name of the knot being used, all I really know is how to do it. Sure , it might damage the cord a little bit over many years of doing this, but look at the damage you're doing to your cords by letting them get tangled. I've had a 100 foot extension cord that I've done this too for about 15 years on it. This cord also lays in the yard year round and has done so for the same 15 years. That cord still works just fine (a few unrelated nicks and dings).
The cord used in this video; however, is only 2 years old and has laid in the basement since I brought it home. I do have another 100 foot one, that I haven't done this way, but it's temporarily running one of my cameras, so it really doesn't get moved. I figure, once I get an electrician in to do some wiring, I'll be able to free it up and use it in place of the older cords I have in the yard.