No, he was specifically talking about me pinging a planet. Twice I've done it and he's said that the enemies can see it. He said that he read it in the readme document that came with the game. I was extremely skeptical of this myself until during that same game, I saw pings on planets suddenly appear without getting the notification that an anlly had done so.
I have not yet tested it in game as I've been more focused on simply playing.
Does anyone know with absolute certainty how the pinging system works?