Hmmm. I see that I can use booleans - at least simple ones like AND, OR, and NOT right in the simple search box. Wooo hooo! Just like in big time DAMs!
I don't have a broad enough test catalog, or enough available brain cycles on a Sunday afternoon, to see if I can do a nested search statement or a fielded search right in there. But we're clearly on a good course here.
And a space defaults to an AND, just like it should.
I'll explore further in a few days. Being able to do any search right from the simple search box would be a wonderful thing for frequent users who can keep the syntax fresh in mind. But those of us who suffer from CRS will still need a little GUI help :-)