For Champion Points, under Ritual we have:
1a. Piercing - Increases the amount of Armor your physical attacks ignore
1b. Precise Strikes - Increases damage and healing dealt by Weapon Criticals
And under Apprentice:
2a. Spell Erosion - Increases Spell Penetration
2b. Elfborn - Increases damage and healing dealt by Spell Criticals
1a and 2a, 1b and 2b are complements, but the meaning of "spell" is different for each pair.
1a concerns Physical attacks that ignore Physical Resistance. 2a concerns Flame, Frost, Shock, Poison, Disease, and Magic attacks that ignore Spell Resistance.
1b concerns any ability that takes Stamina to cast. 2b concerns any ability that takes Magicka to cast.
Am I correct? I kind of wish they'd sort out their terms.