Working with a client that was quite adamant on the page redirect feature mainly to overcome the design of page move/rename in CQ 5.6.1 Multi Site Manager, that was solved in AEM 6.0 and above, where the page will be deactivated across all live copies.
We had to find how many pages were actually just empty redirect shells. For that i built the below query. Nothing Fancy but useful to find all redirects.
Navigate to /libs/cq/search/content/querydebug.html on your server and run the below code