The article focuses mainly on whether the man did indeed send the Google+ invitation to his former girlfriend. It seems to me that the actual troubling question is whether sending a Google+ invitation can be considered a violation of a restraining order. The bar is far too low when receiving a single inconsequential message that you have full ability to ignore can be considered a form of harassment.
I disagree. A restraining order is precisely meant to bar all forms of communication so that we don't need to decide on a case-by-case basis which communications violate the order, which would lead to highly unequal enforcement with some people being punished for things that others are not punished for.
Then again, I don't live in the USA, and the concept of a restraining order is a bit alien to me since it's not something heard of as much over here. There surely is some cultural bias at play.
I don't think it's too much to ask for courts to decide on a case-by-case basis. Establishment of intent is one of the main things courts exist for.