Goal:
    x : V.t  p : VSet.t  a : V.t
  ============================
   ((x = a \/ x = a \/ VSet.In a p -> x = a \/ VSet.In a p) /\
    (x = a \/ VSet.In a p -> x = a \/ x = a \/ VSet.In a p))


DEBUG:Going to execute:
fun flags solver =>
             <Coq.Init.Tauto.tauto_intuit> flags
              ltac:(<Coq.Init.Tauto.reduction_not_iff>) solver