The code was previously confusing focused and presenter tiles quite a bit, and also had a couple different spots that would mistakenly engage 1:1 layout behavior when you're alone with your own screensharing feed.
This was a confusion between indicies of the tile and the tile position:
the spotlight tile is the 0th TilePosition, ie. the tile with order
0, not the tile with index 0.
Also comment one method to hopefully make this slightly easier to
understand.