I finally got a chance to finish watching this. I am truly impressed by the amount of thought that went into this episode of ST:TOS, and that the director could accomplish so much with such a limited budget.
I first watched this episode as a child, so the astounding dramatics and some very subtle points were lost on me then. And when I grew up, all I saw were the cheesy special effects. But this video has made me see the vast amount talent that went into creating this single one-hour episode.
And props to the special effects department for creating a very scary "bad guy" out of virtually nothing. The doomsday machine looks evil almost as if it is evil and not just a mindless machine. Perhaps that's why Commodore Decker couldn't decide if it was a living being, a machine - or neither, but more like a devil straight of the depths of Hell.
"I absorb energy like a sponge everywhere I go. It allows me to see the world and my purpose in it." Zak Bagans, Ghost Adventures (INFJ)