YES

Problem:
 app(app(app(uncurry(),f),x),y) -> app(app(f,x),y)

Proof:
 DP Processor:
  DPs:
   app#(app(app(uncurry(),f),x),y) -> app#(f,x)
   app#(app(app(uncurry(),f),x),y) -> app#(app(f,x),y)
  TRS:
   app(app(app(uncurry(),f),x),y) -> app(app(f,x),y)
  CDG Processor:
   DPs:
    app#(app(app(uncurry(),f),x),y) -> app#(f,x)
    app#(app(app(uncurry(),f),x),y) -> app#(app(f,x),y)
   TRS:
    app(app(app(uncurry(),f),x),y) -> app(app(f,x),y)
   graph:
    
   Qed