Goal:
    s' : VSet.t  t0 : VSet.t  a : V.t  H : VSet.In a s'
  ============================
   (VSet.In a t0 \/ VSet.In a s')


DEBUG:Going to execute:
<coq-core.plugins.ltac::auto@0> $1 $2 $3

Goals:

DEBUG:Going to execute:
intuition VSetDecide.MSetDecideAuxiliary.fsetdec_rec ||
             fail 1 "because the goal is beyond the scope of this tactic"