Goal:
  
  G : t
  HI : invariants
  H : VSet.For_all (fun x : VSet.elt => lsp x x = Some 0) (V G)
  x : V.t
  p : PathOf x x
  Hp : weight p > 0
  hw : 0 < weight p + sweight (spath_refl (V G) x)
  Hq := weight_simplify p (spath_refl (V G) x)
          (transitivity (VSetProp.union_sym (V G) (nodes p))
             (transitivity
                (VSetProp.union_subset_equal (s:=nodes p) (s':=
                   V G) (nodes_subset p)) (reflexivity (V G)))) hw
     : 0 <
       sweight
         (simplify p (spath_refl (V G) x)
            (transitivity (VSetProp.union_sym (V G) (nodes p))
               (transitivity
                  (VSetProp.union_subset_equal (s:=
                     nodes p) (s':=V G) (nodes_subset p)) 
                  (reflexivity (V G))))).π2
  ============================
   False


DEBUG:Going to execute:
match goal with
           | _:0 < sweight ?qq.π2 |- _ => set (q := qq) in *; clearbody Hq
           end