Honestly sometimes I wonder what goes through psychologists minds at times!
I can honestly say that breaking up from my best friends at school has made no lasting negative impact on my life, it's part of life! It's these sort of building blocks that help you through bigger break ups in later life.
Its going to have a bad effect on the kids that do form close friendships because they will be breaking the rules, how on earth can they enforce it? Most kids will already have best friends, what are they going to do with that!? It's crazy lol