“The pauses were him listening to instructions from his earpiece.”
That’s exactly what it looked like. Not that he’s not capable of taking an eon to gather his thoughts. It just seemed he was waiting to hear someone else’s thoughts. The macho sounding phrase “..to the gates of hell.” loses a lot of it’s grit when you precede it with ten minutes of stutter and drooling.
Did you notice his VERY weird grin after he got that phrase out? It was almost like he was proud of himself for getting it out without screwing it up. It struck me as a very odd time to grin -- maybe the Cackling One is rubbing off on him.