SVHS said:

It's interesting what Mike said about the danger of releasing the Legacy edition. It's as if Lucasfilm have been keeping an eye on the fan restorations up to now but generally letting them pass.

Legacy seems to be a unique case. From what I can tell, Mike knows or is in contact with people at Lucasfilm and folks who worked on the original SW, and he has discussed Legacy with them. He also has had access to archive materials (at some point, at least).

I'm sure the overall quality of Mike's work indeed makes it more of a commercial concern. But as far as awareness of the project goes, it seems like he directly told the people who would be in a position to caution him.