The AA 'Enhance: Sacred Armor' says it increases the max health bonus by x% but my spell 'Sacred Armor' only provides a mitigation buff, there is no HP increase. According to eq2 wikia, there should be a max health buff as well: Increases Max Health of group members (AE) by X Increases Mitigation of group members (AE) vs physical damage by Y Without the health bonus, it makes the tier 1 AA useless.
Its only on Kaladim that there is no health buff attached to Sacred Armor. Live still has health, either as a flat number or on the top tiers of the spell it gives addition health based on stamina. Side note: Templar, Fury and Warden versions of the spell also have no health buff on Kaladim. Shaman still have a small ward associated with their versions of the spell, though.