YES

Problem:
 b() -> b()
 a() -> h(f(c()),h(a(),f(c())))
 f(f(h(a(),h(b(),b())))) -> a()
 h(c(),c()) -> b()
 b() -> h(f(b()),b())

Proof:
 Uncurry Processor:
  b() -> b()
  a() -> f5(f5(h(),f5(f(),c())),f5(f5(h(),a()),f5(f(),c())))
  f5(f(),f5(f(),f5(f5(h(),a()),f5(f5(h(),b()),b())))) -> a()
  f5(f5(h(),c()),c()) -> b()
  b() -> f5(f5(h(),f5(f(),b())),b())
  Ground Confluence Processor:
   NFP by decision procedure.