If he knows his stuff he should understand how important network security is. With no router password it's much easier to see what PC's are connected to the network and as you have seen their most recent visited sites. If you have control of the router you can easily change firewall settings and port forwarding allowing anyone from the outside to gain access through your own internet connection.(Original post by orangeboy)
Because he knows his stuff doesn't mean he has to put password son the router that no one knows but him and look at other peoples browsing.
I decided to check and it looks like he can not see what I have been on.
My router too only records the lasts so may websites and they get overrided y other in time.
Half of the top 10 aren't even RG...