Let's say that someone has the domain abc.com and also a subdomain something.abc.com. Something.abc.com is a wordpress theme demo.
Can the subdomain something.abc.com simply be added to the abc.com custom menu, just like any other link can be added to its custom menu? (Yes? No? Why?)
Yes, perhaps a simplistic question, but I keep seeing so many complicated and differing answers to this very basic question. Is WPMU really necessary for something like this? (Yes? No? Why?)