Universal iOS app + Main.as document class question

Hi! I have googled this but can't find anything. There was an Adobe blog on multiscreen development but I couldn't find enough detail to answer my question.

Is it possible to create two separate .fla files with shared assets - one at iPhone screen size and one at iPad screen size, with shared files and classes, the only difference being the layout of the screen, and then call something in a main.as document class somewhere that just checks for iPhone vs iPad and loads the proper file? Basically, is it possible to create a universal app and still have WYSIWYG control over the interface (instead of, say, programming the x and y coordinates of every object on stage based on current stage height and width)?

Sorry if this is a stupid question, I'm a noob.

Thanks!