You are so right. I just checked mine and verified the TA scale is being reset, just as you said. I've had mine set to 0.5. I set them all to 0, turned on the camera, and the TA scale is back to 1.
I don't notice any difference whether those settings are 0, 0.5 or 1.0, so I think I'll just set them all at 1.0.