Decaying Hex doesn't work with aura curses

Even if it probably should, since aura curse is still a curse, so why not?

1. Get any curse, add Decaying Hex, curse any mob
Expected: mob take damage
Actual: works as expected

2. Get Blasphemy, socket curse there and apply Decaying Hex, walk close to any mob
Expected: mob take damage, but maybe less this time (because reduced curse magnitudes in Blasphemy)
Actual: nothing happens. Decaying Hex doesn't apply.

Note: While in inventory, Decaying Hex shows that it can't be socketed in Blasphemy, but when you hover over empty socket in it, there is no warning display "Cannot be socketed here". Also, there is nothing in the decription anywhere why this shouldnt work. After all curse, even when aura, is still a curse.