Shadow Bite

so i was wondering about our new skill shadow bite . the description says this
Debuffs the target, making the next two skills they cast within 30 seconds have 1 minute cooldown.

What if you use shadow bite on a player then that player the first skill or 2nd he uses is a skill that got a cooldown longer than 1minute? example can be like cornered beast barb skill that have a cooldown of 5 minutes. What would the cooldown of the the next corner beast will be? 6 minutes ( original 5min+1min more of the skill ) or reduces the skill cooldown to 1minute. because if it reduces it to 1 minute you could actually help the enemy instead of hurting it