I actually always had that. I just made it several slides.

I also disagree on which solution is best. I've seen multiple programmers try to implement that function and mess it up. There are a number of subtle requirements you have to get right, and I don't think there is any clearer presentation of how to get them right than to show code. I'm not concerned about the common case being wrong. I'm concerned about the production hook going missing, programmers doing the random assignment as $person_id % 2, and other similar mistakes.

I'm leaving the pictures in. I've asked a number of people for feedback, and the consensus of most of them is that the current pictures work well. While I agree that they can be a distraction for someone who is getting lost, I have points where people can resynchronize. And the talk has multiple audiences within any organization, I expect people to lose interest when I'm presenting about stuff they are not interested in. I'd like them to remain somewhat entertained, and then I'd like to get their attention when we move on to a section they care about.