That is correct. Ever noticed how your usual household items have braided connection cable? Or extension cords? Now, after all the reading I have been doing lately about ballast and various types of MH
systems, it seems like gauge 16 and 18 are popular for hook ups between ballasts and lamps. Probably are braided too, tho I have not yet seen/touched an actual ballast/lamp setup. But that should change in the very near future.
Anyway, as usual, I talk too much.
So, the short answer is "Yes". :P But if he does not have access to the same gauge of wire, he can substitute larger diameter to connect the parts, like a 14/2 (with ground cable) cable used to make your own extension cords. Most are braided and available at your local hardware store.