I think he's saying, if in the future you want to route web traffic through a CDN, using a CNAME, instead of directly at a specific server, using an A record, y

I think he's saying, if in the future you want to route web traffic through a CDN, using a CNAME, instead of directly at a specific server, using an A record, you're going to struggle if you're using the root name, as you can't have root CNAMEs. Damn good reason too! I can't think of a good way round it. Do people like CloudFlare configure using CNAMEs? If they do, this strongly weights my decision, (along with the 'non expert users like www.' argument - though I think as long as you use a .com you're probably okay there).