Goal:
  
  A : Type
  P : list A → list A → A → A → Type
  d : A
  d' : A
  Γ : list A
  Γ' : list A
  a : All2_fold P Γ Γ'
  p : P Γ Γ' d d'
  d0 : A
  d'0 : A
  Γ0 : list A
  Γ'0 : list A
  b : All2_fold P Γ0 Γ'0
  p0 : P Γ0 Γ'0 d0 d'0
  ============================
   (∀ e : NoConfusion_All2_fold A P
            {|
              pr1 := {| pr1 := d :: Γ; pr2 := d' :: Γ' |};
              pr2 := All2_fold_cons P a p
            |}
            {|
              pr1 := {| pr1 := d0 :: Γ0; pr2 := d'0 :: Γ'0 |};
              pr2 := All2_fold_cons P b p0
            |},
      let H := CoreTactics.block in
      noConfusion_All2_fold_obligation_2 A P
        {|
          pr1 := {| pr1 := d :: Γ; pr2 := d' :: Γ' |};
          pr2 := All2_fold_cons P a p
        |}
        {|
          pr1 := {| pr1 := d0 :: Γ0; pr2 := d'0 :: Γ'0 |};
          pr2 := All2_fold_cons P b p0
        |}
        (noConfusion_All2_fold_obligation_1 A P
           {|
             pr1 := {| pr1 := d :: Γ; pr2 := d' :: Γ' |};
             pr2 := All2_fold_cons P a p
           |}
           {|
             pr1 := {| pr1 := d0 :: Γ0; pr2 := d'0 :: Γ'0 |};
             pr2 := All2_fold_cons P b p0
           |} e) = e)


DEBUG:Going to execute:
intro