It is definitely good if you are satisfied with very small profits. Because the more profit you expect in trading, the more greed will grow in you. Because when you have the intention to make a lot of profit, you will not stop trading easily, because at that time any amount will satisfy you. Because of this, if you have a small profit objective and if you select a maximum profit margin, then you can probably reduce your losses in trading because small profits can be gained very easily from trading. But it is very difficult to maintain them if greed works in you, and if you cannot stop trading immediately. So in this case, I will appreciate your friend's strategy. And I can say that if your friend follows this strategy constantly, then even if he cannot make much profit from trading, he will at least be safe.
We are talking about Money here and you and I know how influential it can be. As far as money is involved, greed can not be easily do away with. It's always easier to say than done. I realise this when playing aviator game in one of my favourite gambling sites back then. I initially made up my mind that I will close my position at every two odds but guess what, at first I was able to maintain my stands but within some time, I said to myself that the two odds I set for myself is too small and that was how I started losing my money until I can not longer count my loses. Same thing applies to trading and greed will gradually set in since it has to do with money because human by nature is insatiable.