Taper Enchantment

[Defo]

Hello!

Does anyone know, or can anyone point me to surefire evidence of what Taper Enchantment (ENC spell) specifically does? The general description is that it lowers the duration of spells on target when cast.

It's only 5 mana, so I have been primarily using it to pull (and level Abjuration [You must be logged in to view images. Log in or Register.]), but I am curious to know if anyone has solid info on how much of the duration is removed per cast.

Thanks!