No clue where it originated, I got it from Mule in a Skypechat once.
But what is basically said with that is: "Shut up and die."
Which is just another way of saying: "ENAGAGING!11onE"
So I don't know. Personally I deliver RP here and there, if the other side isn't interested in playing along it's wham bam thank you ma'am time.
I don't really mind if there isn't any or much talk done at all either.
Just want to add that the prior-to-engagement RP one does is dependant on the characters.
I've got a guy who will try to bed every woman in space he meets, especially if she's hostile, so he talks a lot prior to action.
Then I've got a short-tempered Corsair who just blows people up and throws lines out of 300 into the game.
("CORSAAAIRS! PUMP UP THE VOLUME AND GET WITH THE FUNK, FOR TONIGHT! WE DANCE! ON MALTAAA!")
My navylass is one of the cold-blooded professional types, unless if she's drunk or tripping, so she'll never talk much.
Just saying that there is those "silent and deadly" types out there too, and it might not match everyone's characters to talk with the enemy for a few minutes prior to combat.