Single Bullet Theory
Literally, a theory that states when man is set against impossible odds, his final bullet will be on himself rather than his enemies. Figuratively, a plan to "cut one's losses" or make sacrifices as a last resort.
So, yeah, according to Mike's single bullet theory, he's gonna play the market right out to the bitter end and try to cash in on as many stocks as possible; however, things don't look good.
JFK single bullet theory
The act of screwing a blindfolded woman from behind when a friend sneaks in and jacks off on her face. She has no idea where it came from.
"Dude, that JFK single bullet theory we pulled on Sarah the other night was the absolute tits!"