Found it one day following the BSD magical mystery tour bus, thanks markus
I think this goes a long way to explaining it, or at least explains why many what may appear to be reasonably good traders end up not really making it in the end.
The Axiom of the Small Edge:
A trader's long run edge is smaller than he thinks; it is much more akin to a card-counting blackjack player's edge of 1% due to variance, ever-changing cycles, and fear-induced losses.
The Postulate of Trading the Small Edge:
Given The Axiom of the Small Edge, what really matters in money management is that a trader always be prepared, always be able to hold a position with a positive edge that goes against him, and always be able to take the next trade:
Imagine
The worst trading day you've ever had. The seconds ticking by, the disaster scenarios playing vividly out.
Imagine
The blackjack player. His edge is 1% or 2 hands/100.
Imagine
The pressure.
Imagine
The public speaker. Stammering, nervous, unpracticed and unprepared.
Imagine
The blackjack player, the public speaker and the trader as one.
Imagine
Once per month being unprepared: 12 hands Once per quarter succumbing to the pressure: 4 hands Once per quarter not taking the next trade, not betting the correct size: 4 hands
Imagine
The blackjack player giving up 20 hands to the house:
His edge is now -18%
Imagine
The blackjack player and the trader as one.
"His edge is now -18%."
The Axiom of the Small Edge and The Postulate of Trading the Small Edge say that what really matters in money management is that a trader always be prepared, always be able to hold a position with a positive edge that goes against him, and always be able to take the next trade.
That kind of pressure adds up and results can go down the pan even more ~ Food for thought anyway pehaps
Andy