MAYBE
Trs:
 {g(true(), x, y, z) -> f(gt(x, z), x, s(y), z),
  g(true(), x, y, z) -> f(gt(x, z), x, y, s(z)),
  f(true(), x, y, z) -> g(gt(x, y), x, y, z),
          gt(0(), v) -> false(),
       gt(s(u), 0()) -> true(),
      gt(s(u), s(v)) -> gt(u, v)}
 Comment:
  We consider a duplicating trs.
  FAIL:
   Open