So... here we have a knife with +Waltz Potency... that cannot be equipped by DNC. Go S-E! Fits right in with +pet gear that cannot be equipped by pet jobs!
(Yes, I know it's for /DNC. It's still silly! The only jobs I could see maybe using it with /DNC are THF and BRD - RDM has better ways to heal, NIN should be using katanas, etc.)
Considering curing waltz iii should heal like 400, this dagger should cure a plus of... 12.
Thats almost irrelevant, given that you wll be giving up somewhere between 60-140 dagger skill. If cures is that much a trouble, use a stronger dagger to finish faster and reduce the needs of cures, instead of using a weaker dagger with better cures,but you will be punched a lot more till you win.
Subtle blow, on the other side, can effectively makes you endure more, as less tp moves will be used, but still, unfortunelly, ilv should be the first parameter you must consider, suposing youre a dd.