Ran codesign -fs - /Applications/Utilities/Boot\ Camp\ Assistant.app how do I reverse it? I ran codesign -fs - /Applications/Utilities/Boot\ Camp\ Assistant.app as per a post here  and now I cannot launch Bootcamp Assistant at all. Is there a terminal command I can run to reverse this?
There is no undo; permanent changes are made. The only way to resolve this situation would be to replace Boot Camp Assistant with a known-good copy. A simple way to do that is to reinstall OS X using Recovery Mode.