@Brian-E It worked for Miles, and as he was the clear underdog, I don't see why this could be perceived as "disrespectful" - Miles clearly had prepared this as a serious surprise weapon.
I can understand that it would be seen as disrespectful in the inverse constellation, though - for example, if a serious player (but without GM title) gets the rare chance to play against the World Champion, and the champion would play the bong cloud because he's bored - that would indeed be disrespectful.