Interesting to see how different views clash.
However, the more time I spend with trading, the firmer my belief is that strategies, systems, backtesting etc. is not enough. As bill said in one of the post: you need to have good intuition.
I read in a book that you need to spend 3-5 years in a given field to become a master of it. In some fields it may take much longer, e.g. chess. In other professions, it might take less. The key here is that with all the experience you gain, you build up a hidden power of understanding things, called intuition. You cannot use it directly. You just feel it, know it.
That's why bill's system won't work in backtesting. You won't have bill's intuition in the backtesting system.