His attitude is expected. Any player that gets traded always wants to get the win when they face their former team. However, it's not like Armstrong has anything to prove to the Leafs organization. It's not like he didn't get his chances when he was here so if he does well in Montreal, then chalk it up to his fortune finally turning a corner. He wasn't useful in Toronto due to his inability to stay healthy for long periods of time. He might be bitter, but if he has any reasonable side to him, he should understand why the decision was made.