Optimal scheduling for a conference presenter

I go to a lot of conferences. I often wonder what is the optimal time to present? To start formulating the model I start by defining success. In my case I will use ”presentation attended by a fully engaged audience” as my success definition.

The first day tends to be a day for conference acclimation, connecting, and just figuring out how to get around. We have all been in the first brief and most of the audience has the program open planning their conference. There may also be jet lag and transportation delays that complicate getting 100% out of day one.
My winner is the second brief (before lunch) on day two. Everyone has had one day to get into the flow of the conference and can find their way around. After a certain number (different for everyone) of briefs folks usually start getting presentation overload and that usually starts occurring for me after day two. Briefs after lunch have renowned fame for being challenging due to the fact the audience has a full stomach. And of course the final briefs of the day always has folks getting ready for travel and other events.
So for those presenters that got that slot at this conference, congratulations!