DislikedOne of the biggest and most popular US FDM's, Oanda, have never offered buying and selling of one currency pair simultaneously on the same account and they're doing just fine, with some of the tightest spreads (and interestingly lowest leverage) in the business!
The only people this is going to affect are the inexperienced novice nickel-and-dime accounts who think there's some advantage for them to trade long and short on the same pair at the same time. These kind of people tend to be resource intensive as they're the ones who complain the most...Ignored
I will say i don't enter both positions at the same time though. that doesnt make sense, but it IS a great way to protect trades already in profit, which is how i use hedging.