I forgot to post about this, it happened a few weeks ago.
Player X (on my team) placed an offensive tower outside 11 to attack 11. I was already dead so I was watching closely, and saw for sure that when the fog cleared upon construction completion, none of 11's buildings were in range, thus he wouldn't see the tower.
Much to my surprise, 11 comes running out with 5 peons to kill the tower. I called him out on it, and he said "I have towers too." I thought he was busted.
But then I recreated the scenario, because there's no way 11 saw Player x's tower if Player X didnt see his. Except when I recreated it, that's exactly what happened. The tower placement of 11's tower saw the corner of Player X's tower.
I asked Swift about this and even he wasnt aware (He's normally a fairly encyclopedic source). Lambchops you have any idea about this?