Vague Ability Descriptions: Focusing on Blade Debar, intentional or bug?

Blade debar procs about 30% of the chance of the stat, (if you have 67% debar, you can expect about a 20% proc chance). Is this intentional or a bug? The description says "occasionally stops karakuri thread consumption when summoning karakuri."

If this is intentional, my main feedback is that this needs to be spelled out. There are very few instances where vague descriptions are appreciated over detailed ones. I would also argue 30% of listed value is way too low, considering the highest possible chance appears to be 87% (or a 26% proc chance) with talismans and weapons and food. I would suggest that multiple instances of blade debar should be multiplicative, or it should be additive and use a proc/(proc+100) proc chance if we are trying to avoid reaching 100% blade debar.

With previous bug fixes regarding sleep and poison proc chances, there is reason to believe that this proc chance may be bugged as well. The more ambiguity, the worse. We gamers have no way of knowing if this is a bug or intended behavior, and I am hoping for dev feedback.