Basically, is it more accurate to shoot one handed or two?
As suggested, a 2-handed hold seems more accurate for many shooters, but as also suggested (and rapid fire aside), it may simply be because that's the way most people do most of their shooting. We tend to get good at what we practice. I shoot better 2-handed, but I've been practicing 1-handed and am making good progress.
As far as
inherent accuracy, though, I could make an argument for the 1-handed hold, though I'm no shining example myself: The consistency with which a gun moves the instant the shot is fired plays a significant role in accuracy. Since the shooter's grip has a major effect on that consistency, I'd argue that, logically, a 1-handed grip is easier to keep consistent. For example, with a 2-handed grip, you've got 5 extra digits (connected to an extra arm) touching the gun and applying pressure, so each one is applying its own force on the gun and affecting its movement when the shot breaks. To perfect the 2-handed hold, then, you'd have to also develop perfect consistency with those 5 additional digits and 1 arm.
OTOH, there's the additional wobble you typically see with a 1-handed hold, but IMO, that gets better with practice, but never goes away anyway, even with a 2-handed grip. And besides, wobble may not be as important as maintaining sight alignment and a consistent grip.