Dave is looking at Biff Henderson. Biff times him as he runs from the left side of the stage to the right. If he falls below a certain number then he knows it is time to retire.
David Letterman
That man was David Letterman.
The virus enters the host cell in the penetration phase.
Kenny Anderson
Concert master
viruses
Pause the game then unpause it.
He probably didn't want the attention to be only on him.
The first stage in a star's life is as a nebula. As the gravitational forces spin faster, the star enters it's second stage, that of a prostar.
Mitochondria
Someone else runs across the stage before the curtain goes up. Then, Letterman is shown walking out onto the stage. This is his way of proving to his viewing audience that he is capable of doing this maneuver. Prove it to yourself. The "runner" always runs out of view.
alpha