Goal:
  
  A : Type
  P : list A → list A → A → A → Type
  d : A
  Γ0 : list A
  a : A
  Γ' : list A
  Hrel : All2_fold P Γ0 Γ'
  p : P Γ0 Γ' d a
  ============================
   (Some d = Some ?d × All2_fold P Γ0 Γ' × P Γ0 Γ' ?d a)


DEBUG:Going to execute:
f x
Level 2: evaluation returns
<coq-core.plugins.tauto::with_uniform_flags@0>
where
f := fun flags => <Coq.Init.Tauto.intuition_gen> flags tac
     where
     tac := eauto
     of type
     tacvalue
of type
tacvalue of type tacvalue

Level 1: evaluation returns
<coq-core.plugins.tauto::with_uniform_flags@0>
where
f := fun flags => <Coq.Init.Tauto.intuition_gen> flags tac
     where
     tac := eauto
     of type
     tacvalue
of type
tacvalue of type tacvalue