What's wrong with two hands on the yoke if the throttle is set with friction and you are manoeuvring?
Just about everything!
If I had my way I'd take a hacksaw to the inner halves of the yoke on PA28s and 100 series Cessnas. If you need both hands to flare the a/c then you're not able to control the a/c properly as you should have one hand on the throttle. (Arrow 4's excepted, I suppose, yuk!)
TOO