From the way i see it, it is because the entire basic rotation, including the attacks which are effected by Fourfold Feathers and the Esprit Gauge, are in a technical sense, the same skill with different potency changes, which is reason enough for me to not touch DNC outside of any PotD/HoH solo attempts. Or in other words said, DNC feels to me like a sandwich being promised to me but all i got was a slice of bread with no butter and 4 slices of the same cheese.
