We having a huge problem with URL rewrites to the point that it cripples our web cart. This is in part due to a post import script being run. What happens is that due to our site having millions of rewrites, when there is an update, the site will show all versions of an item and allow purchasing of out-of-stock items.

The solution if for support staff to "clean' them up. This requires us to be vigilant, and post a support ticket, and then whatever work the support team has to do to clean them up.

When i asked to have this cleanup done automatically at some convenient interval, they suggested I post the idea here. Automating this cleanup process would save everyone time and effort, and in our case, keep us from having to contact customers and tell them that the item they are trying to purchase isn't in stock. That makes us look incredibly stupid.