Ignore Def % Limit?

Adding my two cents.

 BaM Stats

Additional Info
- Using Quintuple Blow
- Only 20% Ignore DEF from Quintuple Blow.
- Level 0 Ambition
- Assumes Battle Mastery's bonus damage is already calculated into range (Don't remember if it is or not)
- No Buffs or Character Cards

Math (Never sure if I do Ignore DEF calculations right, so someone check me, please)
4574 * 1.4 = 6404 (6403.6)
6099 * 1.4 = 8539 (8538.6)
Min Damage with 20% DEF Ignore (Going below this proves 20% DEF Ignore DOES NOT work)
6404 * (1 - .7 * (1 - .2)) = 6404 * (1 - .7 * (.8)) = 6404 * (1 - .56) = 6404 * .44 = 2818 (2817.76)
Max Damage without 20% DEF Ignore (Going above this proves 20% DEF Ignore DOES work)
8539 * (1 - .7) = 8539 * .3 = 2562 (2561.7)

 Observed Damage

Observed 2114 Damage hit, which is less than 2818, the inherent Ignore DEF in the skill doesn't appear to work.

There, like 10 minutes of work. I would love to see what you achieved in 3 hours.