Sounds like a good common sense solution. You might find a good explanation of the things (there are several) that cause the left yaw in a pilot training ground school book. Don't get hung up on propeller P effect but do pay attention to the effect of the airstream coming off of the propeller and how it affects yaw when it ultimately hits the vertical stabilizer (rudder). If you mix right rudder with the throttle you might also want to be able to turn off the mix when flying at a constant speed or in the 'cruise' mode.

Howard