Yes you get the buffs, but how how math works in this game is not %+%... so it wouldnt equal 15%, but it would be more thean having just 10% or just 5%
How long does the Major Berserk aura last? Five seconds?
5 seconds minimum, potentially 100% uptime though. Most people already get Minor Berserk from their healers, so it's actually closer to 10% increased damage than 15%.
This Bosmer was tortured to death. There is nothing left to be done.