YES

Problem:
 __(__(X,Y),Z) -> __(X,__(Y,Z))
 __(X,nil()) -> X
 __(nil(),X) -> X
 U11(tt()) -> U12(tt())
 U12(tt()) -> tt()
 isNePal(__(I,__(P,I))) -> U11(tt())

Proof:
 Bounds Processor:
  bound: 2
  enrichment: roof
  automaton:
   final states: {10,9,8,7,6,5,4,2,1}
   transitions:
    f60() -> 8*,3,1,2
    __0(8,3) -> 9*
    __0(8,9) -> 9*
    __0(2,3) -> 9*,3,1
    __0(2,9) -> 9*
    __0(8,2) -> 9*
    __0(8,8) -> 9*
    __0(2,2) -> 9*,1,3
    __0(2,8) -> 9*
    U120(5) -> 10*,6,4
    U120(7) -> 10*
    tt0() -> 7*,6,4,5
    U110(5) -> 6*
    U110(7) -> 6*
    tt1() -> 10,5,4,6,7*
    U121(7) -> 10*,6
    tt2() -> 10,5,4,6,7*
    1 -> 3*
    2 -> 3*
    3 -> 1*
  problem:
   
  Qed