Goal:
  
  A : Type
  P : list A → list A → A → A → Type
  d : A
  Γ : list A
  X : All_fold (λ (Γ : list A) (d : A), P Γ Γ d d) Γ
  p : P Γ Γ d d
  IHX : All2_fold P Γ Γ
  ============================
   (All2_fold P Γ Γ)


DEBUG:Going to execute:
fun flags =>
             match reverse goal with
             | |- ?X1 =>
                   <Coq.Init.Tauto.is_unit_or_eq> flags X1; constructor 1
             | H:?X1 |- _ => <Coq.Init.Tauto.is_empty> flags X1; elim H
             | _ => Ltac.assumption
             end