Right now we don't distinguish between phys and elemental damage after damage shift has occurs. This means all mitigation applies to all current damage you are taking, regardless if some of it has been shifted to elemental already. This will take a bit of logic and UI work because some mitigation, like armor and abyssus only apply to physical damage, while some effects like shock and fortify apply to phys and ele.
This is being re-worked as part of splitting up elemental damages, so no mitigation affects elemental damage, which is still a bug, but it's less weird than armor affecting elemental damage.
Right now we don't distinguish between phys and elemental damage after damage shift has occurs. This means all mitigation applies to all current damage you are taking, regardless if some of it has been shifted to elemental already. This will take a bit of logic and UI work because some mitigation, like armor and abyssus only apply to physical damage, while some effects like shock and fortify apply to phys and ele.