Some projects have sheets that need to be mirrored instead of rotated. Example would be on multi-family or hotels where you have a sheet that shows a unit type, but on the blueprints that unit type comes with multiple directions of layout. The close up unit typically just displays as a single layout.
Mirroring a page would be helpful for us too. Some buildings are a different type just because of a mirror and being able to mirror the page prior to overlay would help us to make sure there are no differences.
Crazy enough... I just hit this scenario this AM as well