Yeap, as simple as that, and like Robert pointed out, and mentioned before 
the 3-wire feeder was only allowed as an exception pre2008 NEC. After that, it always without any exception, had and has to be installed as 4-wire feeder.
A 3-wire feeder is still safe and okay, but only in old installations (pre NEC 2008).
There, we said the same thing 15 different ways. If someone is still confused after reading this thread, god help them!