I always thought that was "just do it
What comes to mind here are a great many other things, especially the way back in high school we would refer to the act of sex as "doing it" when gossiping.
Also, those of you familiar with the fabulous Aeon Flux
series may remember the episode in which Trevor Goodchild
cloned Aeon so he could have one of her for himself.
His attempts at recreating Aeon continued to be unsuccessful because he couldn't seem to capture her ambivalent (and ass-kickin'
) attitude towards him.
Eventually the real
Aeon infiltrated his establishment as always and masquerade
d as one of his docile clones. She accomplished this by throwing herself on the bed before him and begging:
"Use me Trevor....DO IT!"
The desperate, breathy and sexy
way she emphasized those last words have caused me to picture the scene whenever I hear the phrase "do it" emphasized. It may also indicate how frighteningly obsessed
with that series I am.