That is very tough, imho. Either you take advantage of high volatility or low volatility, but to be able to profit in both regimes is hard. Unless you measure volatility dynamcally and adjust on the fly ... Then it's like switching between two different systems. Would be curious to hear your thoughts on this.
Exactly what I do in my algos. The system skips trades when valatility of instrument is too high/low.
That's because most trader psychology books don't actually tell you HOW to work with emotions, only that you need to. As far as people not needing to work on their mental side of the game and relying on an edge, all top athletes work with sports psychologists, so do the top traders. Edge alone will never keep you in the trading game, because if you can't execute your edge due to mental hangups then you don't have an edge on the market, the market has an edge on you.
Then it is clear that you are making huge mistakes or cheating. I did manual backtesting and results were in line with the stats of backtesting. Within a reasonable error range. If you should enter when two EMA's cross, then you should not miss it. It is clear: when the 2 EMA's cross you should enter. Follow the rules. Backtesting can result in problems too. I saw backtests that where profitable while real trading was not. Reason was programming errors which lead to complete wrong profits that did not exist in reality. Programming brings risks too. Mind can also see problems that lead to loss of profits, while algos just do the numbercrunching and traders lose all contact with what really happens. I improved my system by analyzing trade by trade manually what happened. I understood each trade, an algo does not understand any trade but just executes without thinking.
You just explained what to do. Now you only have to do that. A good system exists of sub systems that each are designed for specific market conditions. There is no on fits all system that works optimal. You don't cut all kind of wood with just one kind of saw. You don't screw all screws with just one kind of screwdriver. That's why there are for each tool a number of varieties. To optimize the result.
How did you do that? You went through charts from previous days? I find it removes the context out of the picture. Don't you ever override your system based on current conditions? Lots of it is gut feel, but maybe that's the problem
I don't use charts, I trade based on mathematical models that generate values. These values generate trade signals. I don't watch charts of past, I watch raw data from past. I never override my system, the only thing that can happen is that I stop trading when things are not clear for me. So no guts feel at all. The computer generates always the same values, no matter how many times I do a backtest of the same period again. Logical as 1+1 always equals 2, there is no interpretation possible.
In such case, when does psychology/emotions come in play for you? I have no problems running fully automated system on intra-day timeframe as it just does what it's supposed to and I only monitor for outages or any abnormal behavior(overtrading, pnl swings, position sizes, etc)