YES
Input TRS:
      1: f(a()) -> f(b())
      2: g(b()) -> g(a())
      3: f(x) -> g(x)
Number of strict rules: 3
Direct POLO(bPol) ... removes: 3
      a 	w: 11799
      b 	w: 11799
      f 	w: x1 + 8856
      g 	w: x1
Number of strict rules: 2
Direct POLO(bPol) ... failed.
Uncurrying f g
      1: f^1_a() -> f^1_b()
      2: g^1_b() -> g^1_a()
      4: g(a()) ->= g^1_a()
      5: g(b()) ->= g^1_b()
      6: f(a()) ->= f^1_a()
      7: f(b()) ->= f^1_b()
Number of strict rules: 2
Direct POLO(bPol) ... removes: 4 1 5 7 6 2
      a 	w: 1
      g^1_b	w: 1
      b 	w: 1
      g^1_a	w: 0
      f^1_b	w: 0
      f 	w: 2 * x1 + 21241
      f^1_a	w: 21239
      g 	w: 2 * x1 + 7723
Number of strict rules: 0