A non-magic healer

[Malkria]

Just to clarify, do you by non magical healer do you mean Gameplay wise (uses TP/TP & Mana) or theme (Magitek, Dance, chemistry, etc etc)?

Mostly by theme and having it fall under the disciple of war rather then magic. Using MP doesn't disqualify on it's own for being 'non-magical' as some classes like the Bard uses magic for a portion of it's mechanics even though it still falls under disciple of war.

One concern I have for a lot of people mentioning a healer that heals through damage is not that the damage aspect would be unbalanaced but that there are frequently situations where enemies/bosses become untargrtable while damage is still occurring. This would make it hard to have this healer keep people up during these mechanics unless they had enough other Heals that didn’t rely on damage to keep the party up. I know other games have done similar things before such as Warhammer AoR where there were battle healers, but they at least had the ability to heal if not attacking just not as well? I can’t remember their exact mechanics.

Depends on how you do it sure. Chloromancers from Rift, the example I knew and refer to the most, still had direct heals. Just the bulk of their healing was through doing damage. So if you gave something like only a direct heal and a party wide aoe HoT with the rest being damage orientated healing, I feel it might just work out fine.