simp [restrict']
ρ : Config F
t : TraceRel'
d : Delta'
⊢ (restrict' t d | ρ) = restrict (t | ρ) (d | ρ)
ρ : Config F
t : TraceRel'
d : Delta'
⊢ (({x | x ∈ t ∧ (x.1.1, x.2) ∈ d.add} ∪ {x | x ∈ t ∧ (x.1.1, x.2) ∈ d.delete} ∪
        {x | x ∈ t ∧ (x.1.1, x.2) ∈ d.modify}) |
      ρ) =
    restrict (t | ρ) (d | ρ)