Bungie thinking P2P connections was a good idea ... It doesn't run smoothly at all. There is a reason why its not used for PC games which magically seems to run smoothly. Why they thought a game hosting over 25 million users would work without servers is beyond many of us. Remember all and any of the lag you have ever encountered? Its because of P2P ... just let that sink in.
Definitely the refer a friend system Trying to make us advertise their game for them is just an insult to those who pay for the game.