All I am saying it is foolish to discard a trading system that works, that has been backtested, just because it is experiencing a rough patch. Any trader out there no matter how good, can experience 7 losing trades, one after another. In the same vein, that same trader can win 7 straight trades and think he is invincible and will never lose. No trading system out there is 100% perfect and drawdowns are a natural result of market reactions via pullbacks or going sideways in a trading range. That cannot be avoided. Adding filters can improve or worsen any trading system. Again, you have to backtest it to see how that filter affects that trading system as a whole. It is far better to stick to what already works than, keep changing your trading system trying to squeeze out the last dollar. In most cases, it makes things worst not better.
Actually the number is 10 losing trades in a row, it's the most basic number in trading and if you get that wrong heaven help you and anyone else, which is why if you have a system that generates 9wins to 1loss you end up always net neutral, at 9loss and 1win you are doing arbitrage and need a system that offsets the 9losses to near zero, this is how almost all traders do it except they don't have near zero losses