Yes, but it is the reason why we see so many X*20A rail designs. I personally prefer the single rail power supplies since they're a no-brainer with no rail balancing, but you do have accept the fact when using them that there's a greater possibility that a fault could cause substantial damage than there is with a design that limits the rails to 20A or 30A.
It's not just a convenience tradeoff as most make it out to be, it's also a cost tradeoff.
It is cost prohibitively expensive to put 20A current sensors on all rails for a condition (>20A & <100A) which rarely occurs in real life.
Especially for these monstrous power supplies that require six rails to keep the current limit down. Still, considering the cost of a 1600W silver or gold PSU, I would say it's probably more of an added expense than cost prohibitive on the BOM. I'm not sure what this one will retail at, but I wouldn't be surprised to see it at retail for $300-$400.
