Advanced audio editing for multicam projects (Ronnie?)

I saw Ronnie comment recently on how audio mixing has improved in FCP X when doing multicam projects. I'd love to know if there are tutorials or walk-throughs on this topic, because that's one of those things that keeps me still occasionally pulling out FCP 7 for a project.

My common workflow issue in this arena:

Multiple cameras of a live fine arts production like an orchestra or choir concert (remember, I work at a school). All of these have merely open-mic audio of the event.

I have a Tascam audio recorder which captures four discrete channels of audio: two ambient and two line feeds from the board. These are each recorded to their own AIFF files.

When I dump those four audio tracks and the three independent cameras into a multicam project, my only choice appears to be choosing one of my line feeds as the unswitched audio for the multicam event.

I'd LOVE to be able to mix my four "clean" channels from the Tasam into the soundtrack for the video, but I can't ever seem to pick more than one audio source to be the main audio for my multicam edit.

For my most recent project, because it was very short, I decided to just bring those four channels into Logic and mix them to a stereo track that I synced up with the multicam... but that was cumbersome, especially since I'm new to Logic. It took me forever to even export my mix (finally just sent it to iTunes because I couldn't find any other way to export a stereo copy of the four tracks I'd mixed).

So if there's a better way to do this, I'm all ears!

As always, sincere thanks in advance.

— Mike

Thank you, sir!

Great bit of reading there — much to think about. I appreciate the input!

— Mike