My friend loves opening different trades at a time, most at times is difficult for him to control what's should be. Trading on free chart with multiple opening can be very dangerous. Yesterday he experience unusual hit when bitcoin price drops again, four trades loss at once when the market go against him. Personally I don't advise multiple trade especially when you're not familiar with trade
It depends on your friend's risk and reward ratio. If you like to take a higher risk, then you can get a higher reward. So the better option is to control the risk and reward ratio.
Eg: Higher risk -> Higher Reward or loss
I wonder if his friend traded one or more pairs? It's different when people make multiple trades at a time with the same pair, and when people diversify and get into multiple pairs.
I guess that risk and reward ratio explains everything. It doesn't matter if someone goes with one or more pairs, single or more trades, it's about control of risk reward ratio! Those who chase big profits will face higher risks and probably will lose most of the time... those who have control can have fun and harvest profit here and there, maybe nothing big but at least something will come.