Nothing is more true in markets... You should use a mechanical trading system. Nevertheless, I'm not saying you should use an EA or an automated "black box" system. That's other theme that I would like to comment in the future. EAs or another magic box, are just rubbish.
What I'm trying to say in this post is that everybody needs a true mechanical system for trading. A system that really analyzes the market and provides a valid entry or exit point, keeping any kind of emotion out of the equation. Letting almost all subjetivity aside. Why I said almost? If you remember, I said before, and still convinced... the trader just has to know if a position would work out or not, or a "feel for the numbers" as I've read in some book. Due market is really mercyless, this is really difficult for a beginer and specially if real money is on the line.
How a trader can be positive about some system? It's not quite easy. The only way that I could figure it out is by paper trading or backtesting... in multiple timeframes and pairs, for several months. When a system has reached our expectations about its performing, we can test it in a real account which should be small, and the trader should be aware (or willing, I would say), to burn it. Always with proper money management; without emotions, though.
How a trader can be comfortable with a system? I could say that with several months of testing that system. My personal point of view is that a trader should feel good and comfortable with a system if it was developed by himself. And that's what I'm trying to do.
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