The argument from the Bruins were that they did not throw a stick to a player... that they threw it on the ice. They are technically correct.
I understand the penalty on Michkov and the bad blood afterwards from the shot after the whistle... the only problem is that I did not hear a whistle until after he sent the puck (maybe it was missed on the broadcast).
EDIT: 605(b) covers that this is definitely illegal. The casebook examples come up a little short, though.