I’ve noticed that whenever I go healer and I DPS full-time while maintaining heals, I usually get 2+ commendations. If the tank is using proper cooldowns and stance swapping, I’ll comm them on my healer. I think the reason why a healer may get commendations overall is that a healer dps vs not dpsing at all is marginally a bigger difference than a dpsing tank vs a tank in tank stance.