Disliked{quote} No, it's not incredible risky. Only if you put it with some dodgy retail brokers and splitting that money will mean smaller positions per broker which results in higher commission. If he can afford to lose $100k it's absolutely ok to trade with that amount.Ignored
but in the end, you wont pay more commission for several small positions. To my knowledge the commission is always calculated based on position size.
If your broker charge 10USD/lot the commission would be 10USD if you have 10 positions of 0.1lot as well I reckon. Same for spread, if the spread is 1pip it is 1pip but the worth of that 1pip with 1 lot will be exactly the same as the worth of 10 0.1lot each with 1 pip.
But the advantage is building a solid partnership, less things to worry about and overall better execution then with copy trader.