MAYBE
Input TRS:
      1: a(a(x1)) -> a(b(a(b(a(x1)))))
      2: c(a(x1)) -> a(b(a(a(c(x1)))))
      3: b(b(b(x1))) -> a(b(x1))
      4: c(b(x1)) -> a(a(c(x1)))
      5: c(b(x1)) -> b(a(d(x1)))
      6: d(d(x1)) -> d(b(d(b(d(x1)))))
      7: c(c(x1)) -> c(d(c(x1)))
      8: a(a(a(x1))) -> a(b(b(x1)))
Number of strict rules: 8
Direct POLO(bPol) ... removes: 5
      a 	w: x1
      d 	w: x1
      b 	w: x1
      c 	w: x1 + 282
Number of strict rules: 7
Direct POLO(bPol) ... failed.
Uncurrying ... failed.
Dependency Pairs:
     #1: #c(a(x1)) -> #a(b(a(a(c(x1)))))
     #2: #c(a(x1)) -> #b(a(a(c(x1))))
     #3: #c(a(x1)) -> #a(a(c(x1)))
     #4: #c(a(x1)) -> #a(c(x1))
     #5: #c(a(x1)) -> #c(x1)
     #6: #d(d(x1)) -> #d(b(d(b(d(x1)))))
     #7: #d(d(x1)) -> #b(d(b(d(x1))))
     #8: #d(d(x1)) -> #d(b(d(x1)))
     #9: #d(d(x1)) -> #b(d(x1))
     #10: #c(c(x1)) -> #c(d(c(x1)))
     #11: #c(c(x1)) -> #d(c(x1))
     #12: #b(b(b(x1))) -> #a(b(x1))
     #13: #a(a(x1)) -> #a(b(a(b(a(x1)))))
     #14: #a(a(x1)) -> #b(a(b(a(x1))))
     #15: #a(a(x1)) -> #a(b(a(x1)))
     #16: #a(a(x1)) -> #b(a(x1))
     #17: #a(a(a(x1))) -> #a(b(b(x1)))
     #18: #a(a(a(x1))) -> #b(b(x1))
     #19: #a(a(a(x1))) -> #b(x1)
     #20: #c(b(x1)) -> #a(a(c(x1)))
     #21: #c(b(x1)) -> #a(c(x1))
     #22: #c(b(x1)) -> #c(x1)
Number of SCCs: 2, DPs: 6
  SCC { #5 #22 }
POLO(Sum)... succeeded.
      a 	w: x1 + 1
      d 	w: 0
      b 	w: x1 + 1
      c 	w: 0
      #d 	w: 0
      #c 	w: x1
      #a 	w: 0
      #b 	w: 0
    USABLE RULES: { }
    Removed DPs: #5 #22
Number of SCCs: 1, DPs: 4
  SCC { #12 #17..19 }
POLO(Sum)... POLO(max)... QLPOS... POLO(mSum)... QWPOpS(mSum)... Mat2b... failed.
Finding a loop...  failed.