Goal:
    A : Type  P : list A → list A → A → A → Type  H1' : list A  H1 : list A
  ============================
   (All2_fold P H1' H1
    → ∀ (H := CoreTactics.block) (Γ : list A),
        {| pr1 := Γ; pr2 := Γ |} = {| pr1 := H1'; pr2 := H1 |}
        → let H0 := CoreTactics.block in
          let H1 := CoreTactics.block in
          All_fold (λ (Γ0 : list A) (d : A), P Γ0 Γ0 d d) Γ)


DEBUG:Going to execute:
intros p