MAYBE
Trs:
 {    f(x, y) -> g1(y, x, x),
      f(x, y) -> g1(x, x, y),
      f(x, y) -> g2(y, y, x),
      f(x, y) -> g2(x, y, y),
  g1(y, x, x) -> h(x, y),
  g1(x, x, y) -> h(x, y),
  g2(y, y, x) -> h(x, y),
  g2(x, y, y) -> h(x, y),
      h(x, x) -> x}
 Comment:
  We consider a duplicating trs.
  FAIL:
   Open