Funny thing is: it’s not something that I do consciously I don’t think. Not that I’m aware of at the time anyway. BAD trades FOR SURE (those are conscious decisions made to second guess the system and undermine myself!!! LOL!!!). But if anybody asked me I’d tell them that I trade the thing MOSTLY blind (truly believing that to be the case when answering them).
I do believe there’s a fine balance when it comes to taking profits and losses on a discretionary basis. I mean to say you could have a very high probability trading system but taking profits too early could still end up in an overall loss for any given period. At least one thing I can say is that I always take profit at, or better, than the trading system’s bare minimum would have me do (which is easy to gauge in my case as it just depends on an indicator’s closing value). Even on my windfall of a Brexit trade: I’d still have made a profit had I not banked my windfall if that makes sense. And who knows: maybe those years of agony actually taught me something that I don’t know that I’ve learned!!! LOL!!! Guess I’m gonna find out in the next few months.
Oh well. As you say: not helping @TonyFender at all I guess. Then again: maybe it is helping i.e. forget back testing and find a system developed by somebody that has at least some proven track record and street cred. and trade it (which unfortunately excludes 99% of the newly developed wonder systems posted here every other day and certainly those +500% per hour gain systems!!! LOL!!!). Suppose fact of the matter and in contrast with my experience: back testing is also no guarantee of future results (the usual blah, blah, blah) (and certainly not back testing demo data on any time frame shorter than the daily time frame).
I suppose, really, the only insight I could offer that I’m at least sure of is to not get bogged down with anything (including back testing). I suppose (dodgy as it may sound and not backed by any scientific or mathematical principal): something (half decent) will work until it doesn’t anymore!!! LOL!!!