mrmartingale system?

I got this e-mail from this guy promoting his website,and i have heard of this system,but he "guarantees" 17 units of profit a week.He bases it on $10 bets with a starting bankroll of $770 bucks.Is it for real? It sounds like it is a double your  bet system,but i don't know what criteria he uses.I'm sure even okla city or wash in the nba can't lose 6 straight (point spreads),and using one of those teams would win all your money back eventually,but i think he jumps around from team to team/sport to sport.I don't want to pay the 40 bucks a week to find out.Anyone know about this? I expect a few boneheaded responses,but what is the truth?