In a high powered prop plane (or a low powered one with a very light construction) you would have torque to deal with, making it easier to turn to one side vs. the other.
For sure. Although even by WWII fighters had rudder and aileron trim. Not that they’d be adjusted perfectly, nor that you’d fiddle with them while fighting.
But you’d generally want 3-axis hands-off flying at a typical fighting speed and power setting.
I’ll just point out that there have been 1-armed pilots flying fairly substantial aircraft. Not military fighters, but it is possible to manage many aircraft with just one working arm/hand.
When I walked into the hangar to sign up to learn to fly helicopters, Jack the owner/instructor said, ‘You can’t fly helicopters unless you can juggle.’ So I picked up the three juggling balls that were on his desk, and juggled them. He said, ‘OK.’
Personally, I see it this way: Helicopters are to airplanes as motorcycles are to cars.
which is a funny thing to say, Johnny, to me anyhow. I’ve always been told that motorcycle riders make better helicopter pilots, learn it faster or better or something I guess.
Some people would say that motorcyclists and helicopter pilots are completely mental.
‘Me, crazy? You’re the one flying with me!’
There were untrimmed fighter aircraft in use at the start of WWII.
I’m not sure that trim would correctly counter tourque steer in early planes? It’s intended to balance the plane in level flight, I’m not sure it always completely cancled engine torque in turns?
Not disputing either of you, but I’d be curious to learn which specific makes and models had/have a cockpit just one person wide with the throttle(s) on the right or on both sides. My days of peering longingly into any oddball aircraft I found tied down are decades ago now. And wandering aimlessly around a GA airport nowadays will get one arrested.
But IIRC I’ve never seen or heard of this arrangement. What’s got it?
Seems I have seen several but the only one I can remember for sure was an early Pitts that was built by a guy who had it at Harvey Young in Tulsa. ( controls on the right )
So being a home built, most may not count that??
This. It doesn’t even really occur to me that I’m using my “non-dominant” hand to change gear.
Same with guitars - I’ve always found it odd that the seemingly more “technical” part (making the chord shapes) is done with the weaker hand, while the mindless strumming is done with the dominant hand. But then I don’t play the guitar 
I’ve seen lefties play guitar upside down. Which really seems like doing it the hard way.
Going to extra effort to make sure your non-dominant hand does the hard part when for once life would be easier for a leftie if they did it the standard way.
I guess “doing it wrong” is a hard habit to break. 
To my best recollection (it’s been over 10 years now!) the Max-Air Drifter I flew had both a left and a right throttle to go with the center stick. Homebuilt, so not sure if that was an original feature or an owner/builder modification. Like Gus, I’ve seen it on homebuilts, usually ones without in-flight adjustable trim so you can get tired holding the stick steady and being able to switch hands and give one a rest is a pretty nice feature.