The layout of our website has been completely overhauled. The old placeholders didn't make sense anymore, so they aren't used in the new layouts. As a result, most content pages are now empty. All pages still have controls set up in the presentation details, they are just not shown since they are mapped to old placeholders.
What I need to do is go through all pages, take all controls mapped to non-existing placeholders in their current page layout, and move them to the "content" placeholder. This way, content editors will be able to see these controls in the Experience Editor and move them to other placeholders on the page.
Note that some pages have already been worked on, so the controls that are mapped to valid placeholders should stay where they are.
Is there an automated way of doing this? An SPE script, perhaps?