Wendell, I agree there is merit in trying to serve both needs, the newbies and the old hands. Clearly stated, beginner lectures would allow some to slip out and get a bite to eat or attend to other matters and clearly second tier lectures would allow the advanced to focus their attention and the newbies sit back and listen without feeling they "don't get it" since they aren't expected to at that point. We will likely find some newbies who can contribute a lot to the advanced discussions as they may already have extensive document handling knowledge or network skills. For that reason I WOULD NOT separate things into two very separate tracts (as say with two rooms or different days.) Lots of opportunities to cross pollinate would be wise.
