It has as many facts to support itself as a theory as anything else I know of my childhood.
Being aware of a problem is the first step to a solution. But it is only one step of many. That's the reasoning behind the choice I made and why I've stuck with it.
Spies can do that without much human knowledge of each other. Signs, ciphers, hints... The times without a blanket of conceit mean the most. I met him when I joined SHIELD. But I did not get to know him quickly.