I would suggest creating a module <mod> element to be used for blocks of secondary content on a page instead of using <aside> for these purposes. These modules of content could then be styled and positioned using CSS (to be on the side, at the top, the bottom, or wherever) and would be a better structural name than something like <sidebar>. Adding a <mod> element would be more clear and a better name for use outside of an <article> tag and make the definition of <aside> less broad and confusing. An element called <mod> would also be more structurally descriptive so a mobile device, for instance, could list all modules of secondary content on a page to be viewed separately. You could also use CSS to specify not to display any <mod> defined modules when printing, or a browser could even have a built-in user printing option to not print any modules if desired.