Interesting topic, thanks for starting it..
A discretionary approach to scaling both in and out appeals most to me as I find so much of trading is about adapting to the current market activity.
Maybe this guy's 'reasoning' for entering/management/exiting trades could be of value.
SimpleAndHard's Channel - YouTube
his trades this day were huge (see the 'more info' text):
SimpleAndHard's Channel - YouTube
Cheers
Scaling Article
(btw it's just a random web article I found a while back)
I'd like to point out that each individual is different and each strategy is different. If you have a strategy which either hits its target or stops out mostly, you might want to simply hit full size with no scaling at all. On the other hand, if like many you see some degree of MFE even on the majority of stop out trades, it may be worth your while looking at scaling out. Imo, while it may well reduce your profit for winners, it will also reduce your losers(and take a small profit from otherwise losing trades). Trading is about the sum of all parts. It is my opinion therefore that a more stable equity curve is desirable as you can then build your account better through position sizing.
Anyway, read the article and see what you make of it.