Dark Magic
Unholy Knowledge- Reduces Magicka and Stamina costs for all abilities by 6%.
now reads as -Reduces the Health, Magicka, and Stamina costs of your abilities by 6%
Blood Magic- Hitting an enemy with a Dark Magic ability heals you for 10% Max Health. This effect can occur once every 0.5 seconds.
now reads as- When you hit an enemy with a directly applied Dark Magic ability, you heal for XXXX. This effect scales off your Max Health and can occur once every 0.5 seconds.
Persistence- After blocking an attack, your next Magicka or Stamina ability costs 15% less.
now reads as - After blocking an attack, your next Health, Magicka, or Stamina ability costs 15% less.
So why make these hidden changes, if there are not really any abilities that cost health available?
Also on another note, blood magic will only be able to proc off daedric mines to get anywhere near that cooldown.