In 2015, TechCom discussed the possibility that decision-oriented RFC meetings should result in the decision to put RFCs into "last call", rather than be automatically approved in the meeting. We could then agree on a fixed time to close off the discussion (e.g. one week), possibly using subsequent TechCom meetings as the place to finalize the decision.
On 2016-05-04, TechCom briefly discussed this issue in E167. We have basically been using this process for the past few months. We typically announce something is going to "last call" on wiktech-l, then give it one week, then consider it done. We have mw:RFCstatus, where last calls will likely be documented.
We want to issue a call for last calls on call for last calls. :-) Barring substantive objection, we'll consider this RFC approved.