Yes, this makes sense. I suppose if the rigidity is equivalent, which may be more challenging to accomplish with an H-frame, then there would be no difference.
IIRC H frame that isn’t sufficiently rigid can exhibit adverse yaw coupling when running props-in as throttle changes necessary to cause yawing moment induce opposing frame twist. Running props-out causes them to align improving yaw authority.
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I must disagree that the frame must be rigid. Ten years ago I experimented with isolating the arms on silicone O rings in a H frame configuration. At first it had zero yaw control until I figured out what was happening. The arms tilted in the wrong direction so the tilted lift counteracted the motor torque. (There was no such thing as H frame in arducopter at the time). I got in the code and reversed the motors. Worked perfectly and was extremely low vibration. The arms now tilted in correct direction and helped with yaw. The developers then put H frame in the next release.
I have now build several ‘flexi’ H frame types and they have all been excellent.
Here it the first test after reversing the motors 10 years ago.
Question - is there any advantage to having the motors turning in the conventional ‘X frame’ direction?
