Yes, I understand, but still, all you need is to always remember: "minus 10 deg" when setting, or re-setting the gyro. It's no additional work when resetting or resynching.
Then, you can just *read* the map, without any further calculations.
Again, I understand that convention is magnetic, because the magnetic compass is "always right" (within its 10° error). However, I might deviate from original protocol in this one case
