Quote from SteveH:
Donna,
If you randomly pick trades from the population of valid trade setups from a positive expectancy system, it will not alter the long-term outcome of success. The only way it would be possible to do so (with negative results) is if the person has the subconscious ability (i.e., intuition) to consistently choose a greater majority of bad outcomes which, of course, is not random. The converse would hold as well: another person having the intuitive ability to non-randomly pick more of the winners than losers, exceeding the experienced results of someone taking all of the setups in the same time periods.
For example, no matter how hard anyone tries, s/he cannot pick and choose coin flips (from a fair coin) and alter the long-term probabilities of the experienced distribution results. The randomness has no reliance on the participant's timing of when to decide to choose a side. It is "built-in" to the fair coin itself.
So, there are two ways to neutrilize a person's intuition in taking trades from a positive expectancy system which could negatively impact the results: either take all of the trades OR flip a coin, you take the trade if it's heads, pass it it's tails (or vice verse). Then, you're assured of taking random entries from a winning system and your long-term expectancy results WILL mirror those of someone who took all of the trades.