Current wording:
"Delivers an attack with a potency of 780. Potency increases by 80 for each Chakra open.
Closes all chakra upon execution.
Additional Effect: Increases movement speed
Duration: 5s
Critical hits with this weaponskill will not open a chakra..."
As monk has two chakra resources, Chakra and Beast Chakra, that open and close one might think that having open Beast Chakra would count towards the 80 potency increases but it does not seem to do so. In my light testing, this does not seem to be the case, with only the non-beast chakra open count appearing to increase this skills damage.
This means it's either not functioning as intended or that Beast Chakra don't count and you may wish to either reword the skill itself or change the Beast Chakra to another term, like Beast Aspects. This could help alleviate confusion as to how the skill is functioning (if it's intended this way).