Frontlines is ruined by exploits, SE need to fix it

[Toranja]

Issues = Stacking of healers in Frontlines
Possible solution = Focusing one healer
Focusing one healer = other healers being free to do as they wish
Free healers = heals the healer being focused.

Solution deemed a failure. Try again.

DDs focusing on a single target => DPS > HPS
DPS > HPS => HP_t = 0, t -> ∞

Proposal deemed acceptable.