I want to believe Mackenzie occassionally works with Tiffin! Holmes because can you imagine the headache he would get from needing to watch the sexual tension between Sherlock and James, knowing full well that afterward, he needed to drop in on Raffles and Bunny?
My headcanon is that Mackenzie is gay or bi, but being a policeman, he is very careful to keep it underwraps. He's not going to rat others out. But it was fatally dangerous to be gay in Victorian England, and so his blood pressure spikes whenever he witnesses others being so obvious about it.













