I understand how it could be frustrating, but to be honest I didn't notice AN was up until last turn, I though it just went up (got a notification that some global was cast, looked at the list and saw AN). If it makes my actions any clearer I dropped everything I was doing immediately when I saw AN up and threw the kitchen sink at you.
In answer to your query, NAPs are rather loosely defined in the community and what people think violates them (or gives you grounds to ignore them) varies from person to person. My own view is that signing a NAP is akin to saying that we'll stay out of each others way for now...but that is violated by anything that is done to directly disadvantage me. You incite unrest with spies, cast anonymous rituals at me, assassinate my guys, fence me in by taking all the indies around me or put up a global that materially affects me and depending on the circumstances I will feel free to make the assessment that you have not upheld the requirement of staying out of my way. Not that I think there's anything dishonorable about doing that, I'm all for trying to squeeze the most use you can out of a NAP. Just don't expect me to sit around and throw the game because of it.