It sounds like he's complaining that it was telling him to go somewhere he already was.
But being in the same building doesn't mean he was already there. When I'm at work I still want a reminder for a meeting.
He wasn't going to the exploratorium for a meeting. I'm not sure what the solution is, or if there is one, but the point is that it was not useful.
It was in a calendar (this case G+). It's not going to know you don't want a reminder for something because it's not a human and it can't read your mind.
I'd rather have it remind me of things that I don't want to be reminded of than not be reminded of things I do.
It was a Google+ event with about 100 people invited. It felt like it was a cached notification that didn't realize I had already arrived.
The premise of google now is that it can read your mind. It's not my (the consumer) job to be concerned about implementation.
No, it's really not. The premise of G+ is that it predicts what you want to see. There's a massive difference between predicting and knowing.