I was trying to improve performance on a client's web app couple days back and on a certain page added EnableViewState="False" to the @Page directive to see if it helped. So I get a call telling me the page isn't working.
Object reference not set to an instance of an object
You know, the usual. I spent an HOUR tracking it down. I'm so conditioned to stay in the codebehind.CS and alter the @page directive so rarely that it wasn't on the radar.
it is now...