Return of Reckoning

Hello,
I tried to test it on monsters, I can often see centuries of training doing damage but I never notice trained to hunt damage.
Since the two are dots, but centuries of training is spirit damage, and trained to hunt is probably physical? not written on the skill.
So: do they stack together, can they do damage together?
Thank you!

Trained to Hunt proc is displayed as Hunter Strike in Combat log. Dont know dmg type for sure but my bet is physical.

They stack, but TTH is mediocre in comparison since it's physical and doesnt bypass toughness nor armor, so added damage is worthless.

Better use the other trainings ; 5% crit = 5% average damage if you play with pet, and 80 toughness + pet's maximum dps is always worthy.