Let's talk about impact in the one-plane swing. This is the moment of truth. If you want a consistent impact then the one-plane swing is really the way to go, it makes you more consistent.
Consistent Impact: One-Plane Swing
The reason it does is that once you approach impact, the face is already square to the plane. So all I have to do is continue turning and moving my arms. You can see that the face is closing just because it is traveling along that arc. If I were to bring my arms down and pull the handle down in front of me, now you can see the clubface is open, so at this moment I have to use my hands to square the clubface up.
How to Get a More Consistent Swing
I have a lot of crossover right at the golf ball. If your timing is good then you are in luck, if it is not then your shots are too wild. If you want to be more consistent then this is the motion you would want to have coming through your golf ball. You can see my body is turned, my right arm is releasing all the way through to the left.
If I turn this way so that you can see from a face-on shot, this is what it would look like coming down from here, into the golf ball, you can see I am turning and the face is closing on the arc and the right arm gets extended as I go on through. That impact will lead to more consistency and more power, you should try it.