CD and manacost reductions

got back 3-4 months ago and I just noticed this on vdk and cav

For vdk on daunt all skills obviously would get cd reduc so i thought that would mean i would get to cast more skills during the buff after 10 stacks but it seems like the duration is also reduced so i can only cast the same amount of skills casted even when on rav that doesnt have cd reduc.

For cav manacost reduc also seemed to equate to mana gain reduc when on daunt