Good question! I would say you don't have to be but it probably helps!
I’ll admit that I may not have known right off the top of my little ole’ bald head how this was done without reading the explanation. Sure, it could have been a composite.
But this isn’t as easy to do as it may look to some. As those who have tried probably discovered and those that have not tried have no clue. Especially, as Graham mentioned, how easy it is to discover the possibility of “ghosting” and other phenomena that can be less than optimum (read: trash the shot). Then, if you discovered this possibility because you didn’t do it right were you able to figure out why it happens and correct it?
I, too, applaud the technique used to shoot this.