Check if user is authenticated - based on Response NOT Request?

There are a lot of ways to check this as detailed here: http://forums.asp.net/t/1330276.aspx?Check+if+User+is+Authenticated

However they all have one thing in common - they check if the REQUEST is authenticated. 

What if the user is signed out by the action, or, for example, by an error handler? The page then thinks they are authenticated when they're not because the original request was. 

Is there any way to check authentication based on the Response, ie AFTER the controller action has signed the user out?