Regardless whether their strategies work now or later, most systems with short time durations have to be adapted to increase/decrease of volatility. Whereas long term systems might never change, I have not changed entries in long term commodities since made it in early 90s, but have changed risk management as knowledge expands. There is a reason why this is toughest job in the world to get good, but sky is limit for the 1%. Charting started before 1900 and it has expanded and used by many.