It is my guess that he really appreciated that. Said thank you very much may I have another but you were too far ahead to hear him.
Possibly the one disadvantage I have here in town is that most folks displaying that sort of behavior choose to do so when off to my left on a multi lane one way road. Not having a turbo myself I end up with their pipe at my window level and the black cloud moving along. I don't know, if they don't know, what they are doing or if they do know and are just being jerks to a guy in a small diesel with the window down.
No accounting for poor manners.