Not sure time frame you are refering to however it may have been before the add dmg nerf to healing that mostly MA's complained about with their perk heal from red dawn or red dusk?
With heal nano and heal aura perkline and several target perk heals when the dmg add was included yes keepers were extremely good with passive healing and target perk healing. But I think this has been changed so no more dmg adds to healing. Not sure if that is what you were referring to though.