I'm a lefty, so I hold the rod in my left hand for both casting and fighting the fish, and strip line and reel with my right. And I prefer to have my left arm, which is stronger, holding the rod to control a heavy fish.
Here's my two cents on the dominant-hand-should-reel-to-retrieve-line-faster theory: Maybe I could reel a little faster with my dominant left hand than with my right. But a real ocean speedster (bonefish, albies) can swim, what, 40 - 50 mph? I bet NOBO
DY can reel fast enough with either hand to keep up with them if they're charging at you. Good fishing!