Do you think there is a reason Garleans can't use magic?

[Rannie]

Both Alma and Ramza Lexentale don't have 3rd eyes I think? I think I remember it being said his lack of 3rd eye made him insecure. We know his father is a Garlean pureblood, not sure about their mother. It's possible she's was a Hyur from one of the occupied territories

Not to mention CId says himself that only pure blooded Garleans have the third eye when taking you to Garuda