Well, I've never done them, but that's the way I plan on doing it when I start making sweaters. I'd simply apply what I've learned from knitting socks 2-at-once.
You'd use 2 balls of yarn and a slightly longer circ (at least 24-29 in.), cast on for each and go from there. Mirror the shaping. If they were done in the round, I'd use the Magic Loop method.
Everything else would probably depend on the pattern. :shrug: