Is there a way to define Marionette subregions like this? Wouldn't this be cool?

subregions_idea.js

// SCENARIO: i have an overview page with several regions.
// when clicking on an item, an overlay is opened (overview remains in the DOM).
// the overlay has several Marionette regions as well (article intro, article body,
// related articles, its own footer)

// QUESTION: wouldn't it be cool to render views by calling myApp.overlay.mainContent(new ArticleView())?

myApp.addRegions({
   overview: {
     el: '#overview',
     regions: {
       mainContent: '#overview-content',
       sidebar: '#overview-sidebar',
       footer: '#overview-footer'
     }
   }
   overlay: {
     el: '#overlay',
     regions: {
       intro: '#overlay-intro',
       body: '#overlay-body',
       related: '#overlay-related',
       footer: '#overlay-footer'
     }
   }
});