Well - it's really a formula isn't it? (I am stating the obvious I guess)
No. of Wins * average win $ / No. of losses * average loss $
So you can have a few big winners and lots of little losses and do OK, or lots of little winners and few little losers, or any other combo you wish to consider.
Just as long as the ratio is greater than 1, and ideally 3 or more for longer term traders.
The formula also gets away from worrying about single trades. It is looking at portfolio performance over time - the longer the better with a good system. A hundred trades gives a much better picture than 1 trade
regards
Stevo