I'm not so sure it is a joke. The author clearly states it's more for neophytes. And the convention can be explained of using 2π after showing what it all means

I'm not so sure it is a joke. The author clearly states it's more for neophytes. And the convention can be explained of using 2π after showing what it all means by explaining Tau If nothing else, we should at least get a non-separated printing character that looks like 2π connected up, similar to latin dipthongs.