Because we have stacking class known as DN subclass, various masteries are merged into
Armor Mastery of starting class (fighter and mage) > Armor Mastery Lv. 1 - 5
Heavy Armor Mastery > Heavy Armor Mastery of Knight classes
Light Armor Mastery > Light Armor Mastery of Orc Shamans
Robe Mastery > Robe Armor Mastery of Orc Shamans
Due to this adjustment, learning depth/level are changed but you have slight more p.def points than official on most classes. Only rouges after 2nd class and Tyrant have less p.def with light armor.
Knight classes with heavy armor and Orc shamans (OL and WC) with light and robe have same as before.
Relating page on DN- wiki
Mastery (http://dnwiki.dragon-community.net/index.php/Mastery)
Skill List (http://dnwiki.dragon-community.net/index.php/Races_and_Classes)