YES
Input TRS:
      1: b(b(x1)) -> c(d(x1))
      2: c(c(x1)) -> d(d(d(x1)))
      3: d(d(d(x1))) -> a(c(x1))
      4: a(a(x1)) ->= b(c(x1))
      5: b(c(x1)) ->= a(a(x1))
Number of strict rules: 3
Direct POLO(bPol) ... removes: 1 3 2
      a 	w: x1 + 83674
      d 	w: x1 + 58572
      b 	w: x1 + 75307
      c 	w: x1 + 92041
Number of strict rules: 0