Single Bullet Theory Edit Meaning

1.

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.