Damage numbers show total damage instead of each attack's

[Buzz Killington]

This is counterintuitive, when I attack a monster and hit for 1000 damage I see that number, but when my pet/companion attacks the same monster in the same round (for let's say 400 damage) the number then shows 1400.

The first time I saw this I thought that my pet was doing 1400 damage on its own, but the enemy health bar moved very little compared to my hit.

My expectation is that the damage number shown would tell me how much that individual attack moved the health bar down, not the total damage taken in a round.