Source : Webster's Revised Unabridged Dictionary (1913)

Deftness \Deft"ness\, n.
   The quality of being deft.                     --Drayton.

Source : WordNet®

deftness
     n : skillful performance or ability without difficulty; "his
         quick adeptness was a product of good design"; "he was
         famous for his facility as an archer" [syn: {adeptness},
         {adroitness}, {facility}, {quickness}]