That would make for terrible UX, and I'd expect most users to just shrug it off as your website being weird, so it wouldn't even help you "catch pages that use

That would make for terrible UX, and I'd expect most users to just shrug it off as your website being weird, so it wouldn't even help you "catch pages that use the wrong protocol". Why not just do the redirect that you know is right, but log it (with referer, so you know what needs fixed)?