@EdwinAshworth: that question is about be vs are, this one is about a different distinction. Although I cannot see why anyone would want to add to to that sentence...
– oerkelensMar 18 '15 at 11:24
medica's 'The subjunctive clause can be a mandative subjunctive which is a clause following a mandative word (expressing a demand, requirement, request, recommendation or suggestion) and usually, but not always, begins with 'that' and contains a bare infinitive.' [bolding mine] seems quite adequate to me. This question has in essence been asked before and already has an answer.
– Edwin AshworthMar 18 '15 at 17:13