Yes, at the calibration volume those are the appropriate corrections. But if the sensitivities are different, how do those corrections still apply perfectly?
Those corrections still apply because the sensitivites do not change, regardless of how different they are.
Is this totally linear correction really working no matter if it's distance or sensitivity that's calling for those corrections to be made at reference volume?
Yes, if prior to calibration your L speaker is 5dB louder than your R speaker (regardless of sensitivity or distance) then L will be 5dB louder than R at any and all volume settings. Same goes for speakers that both at the same level. Once they are corrected to the same level, they will remain on the same level at any and all volume settings.
