Combat Potency

From wow.incgamers.com

Talent: Combat Potency
Effect: Gives your successful off-hand melee attacks a 20% chance to generate Energy.
Statistics: Rank 1 = 3 Energy, Rank 2 = 6 Energy, Rank 3 = 9 Energy, Rank 4 = 12 Energy, Rank 5 = 15 Energy.