🔷 Trade with self made policy don’t copy others style of trade, what works for you doesn’t work for me.
I agree with your other points except for this one. Controlling emotions and using stop losses are very important in trading. We need to have some kind of rules in place to but rely on our stomach. Our gut feelings are not going to make the right decisions and in the long run we are likely to lose money.
But for new traders it can be very helpful to look for other strategies and try to copy them. Why shouldn't a strategy that works for you not work for other people? We all face the same market, the same prices. A profitable trading strategy can be used by anybody. Sure if there are enough traders doing the same trades then the return will eventually disappear, but it's still profitable in the beginning.
Copying a successful strategy is not wrong and can make us a lot of money. The only thing I recommend is to make sure that we understand the strategy before using it. Because if the strategy fails we need to understand what went wrong and if we can fix it or need to abandon it.
Personally I think the point of the OP stands, people using the same strategy can obtain very different results, there are several reason for this, one of them is that if you are only copying what someone else is doing then you do not know the reasons for their actions, and if you do not have an understanding of why a trade must be made or avoided then you are not going to have confidence applying the strategy in the exact same way.
Which leads us to the most common reason why people fail even if they use the same system, and that is that people cannot stick to it, they let their emotions to take control of their trades and they lose money because instead of closing or opening a trade when they should they decide against it and lose money because of this.