But in the 9th Circus? Good luck with that...
An unmasking of Obama would create a legal meltdown. Acts of government from 1/20/09 would be accepted under the “de facto” principle, but Congress would need to pass an omnibus bill (containing all legislation passed from 1/20/09), and Biden would need to sign it. A significant faction of Congress would want to pick and choose which legislation gets passed, since the lower House has changed hands. Very messy situation.
Some people like messy situations.