I saw it many times in '82
, and again night before last.
One thing about that scene, that big music swell seems to make the
"yell" more intense, then (I think) the second is an echo, with the music following again. (who knows what the intent was, that was always my impression).
When all the parodies of that scene began, I always thought that Kirk was over-acting on purpose, one to sell the lie/exaggeration, and to mess with Khan.
If memory serves, the audience was always very serious.