Garyou Tensei is acting pretty weird for me?

So it said garyou tensei has increased damage if armor break is inflicted, so it would be logical for katana user like me to use zantei settetsu to armor break and use garyou(and i have also added kairiki ranshin for extra damage before starting this combo) and yes i did armor break the boss, but the damage of garyou did not change at all compared to how i used it without armor break inflicted,why?

 

Are you sure you're using it at same stacks when you were comparing? There's also the question of your stability. Did it graze on one or both attempts? How about the buffs present? Were there any consumable or skills that expired? Are you sure Armor Break didn't expire when Garyou hits? Armor Break only have 5 seconds duration. How about proration?