Undesirable flashing
On my computer, the situation is still far from ideal.
Albeit very fast, there is some undesirable flashing on the screen while the stage is being set.
You wouldn't want your viewers to have to contend with that, so we will need to make at least one more improvement to the method.
In the next version of the program, we will cause the objects to be invisible while the stage is being set.
We will make them fade into view at the end of the setTheStage method.