Youâre right on with the roulette comparison: all bets are balanced and youâll break even in the end, independent of positions, minus commissions and slippage (the casinoâs take). Assuming, of course, the foundation of the pricing model is correct: random, lognormally distributed price changes.
After reading about fat tails yesterday in McMillan's book, I'm certainly leaning towards buying rather than selling. It's like a roulette table where the 0/00 expand on occasion like a PacMan trying to take a bite.