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
  H := {|
         pr1 := d0;
         pr2 :=
           {|
             pr1 := d'0;
             pr2 :=
               {|
                 pr1 := Γ0;
                 pr2 := {| pr1 := Γ'0; pr2 := {| pr1 := b; pr2 := p0 |} |}
               |}
           |}
       |}
    : sigma
        (λ d : A,
           sigma
             (λ d' : A,
                sigma
                  (λ Γ : list A,
                     sigma
                       (λ Γ' : list A,
                          sigma (λ _ : All2_fold P Γ Γ', P Γ Γ' d d')))))
  e : {|
        pr1 := d;
        pr2 :=
          {|
            pr1 := d';
            pr2 :=
              {|
                pr1 := Γ;
                pr2 := {| pr1 := Γ'; pr2 := {| pr1 := a; pr2 := p |} |}
              |}
          |}
      |} = H
  ============================
   (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:
pattern sigma rhs
DEBUG LTAC Evaluated term: {|
                             pr1 := d0;
                             pr2 :=
                               {|
                                 pr1 := d'0;
                                 pr2 :=
                                   {|
                                     pr1 := Γ0;
                                     pr2 :=
                                       {|
                                         pr1 := Γ'0;
                                         pr2 := {| pr1 := b; pr2 := p0 |}
                                       |}
                                   |}
                               |}
                           |}