I never understood MYSQL further than copy-paste from existing basic cripts… and I don't understand WP queries!!
There are SO many functions that do the same out there, and I've tried them all, no success :( and now I realize nothing works because the queries weren't designed for that :( and the solution is probably to build a custom one, and although they seem a 8-line script, I don't understand them!
Would you write a few lines (I saw them being a few lines only!) for a custom query that "switches" blog?, something like:
"Select the only page from blog1 that matches this page_name" (or title)
I'd use it then inside the loop, since It's mostly content, but I'd probably recycle it to get masthead content from a unique page (in the other blog) which resides in a page so it can be edited.
In other words, that would solve me the whole "alias" or "mirror" pages I was looking for.