Money management won't help make a bad system good, if a system loses money there is no way to turn it around. Expectation is a mathematical concept based on the win ratio and the relative size of wins and losses.

The formula for expectation is:

    Expectation = [[1+(W/L)]*P]-1

Where W is the average win, L is the average loss, P is the win probability.

What money management can do is greatly expand the profitability of a system that does work, maximising the profitability of any system with a positive profit expectation.

Obviously the expectation calculation is only really useful based on historic testing, it is possibly not useful in real-time trading, only for a historically rating a system.

Knowing that trading is just a numbers game, you can stop looking for a trading holy grail technical analysis technique, professional traders don't use them, instead concentrate on making sure that the method being traded is logically sound and has a positive expectation. A good money management system will turn a rather ordinary but still profitable system into something far more successful.