Regarding Petkos 6 month and 1 month, I believe Petko has determined through experience that it works well and has some logical sense but I’m sure he will confirm his reasons when you reads this.
My feel for these date ranges is that the longer filter is serving as more of a general robustness test of the EA and then the shorter filter serving as a selection based on what is performing best on a shorter more recent timeframe. Wether 12 months and 2 months or 4 months and 2 weeks may perform better I don’t know.
Also It’s not to say that the Ea won’t perform well after a month but just that the process should be repeated on a reasonably frequent basis to adapt to changing market conditions.
I agree with the logic of the approach and certainly used to get good results on demo when I started out using it. I remember my first months results were 50% profit that steadily grew over the month (using 10k account and 0.1 lot size) but I personally would be at least halfing my lot size in order to reduce my risk.
I would practice it for a few months and see how you get on (using demo account of course). Fairly easy to run other tests alongside it as it only takes a couple of hours at most once a month.