And there we are, at the same quandary.
Backtesting has become completely pointless now. Did the "backtesting" from 2009 to 2017 work? Really? It did? Cool!
Did the backtesting from 1929 to 1986 work? It did? Really?
Did all of those backtests apply those same rules to 2018? Did it work? Really? Prove it. I bet it did not. It is why so many people blew up this year. There has been unprecedented point movement in 2018. In my head, percentages mean nothing in derivative back testing...Only number of ticks. If I am blatantly wrong, prove it.