Interesting subject though, as an approach controller, on the sector that I work we only protect the missed approach when weather conditions are marginal or below circling for the cateogory of aircraft flying the approach. Having said that, most of our releases of departures are given to the tower as a "Released your sep" on the inbound so the tower won't clear an aircraft for takeoff until they see the inbound or use a "composite" visual sep. Once they have seen the inbound (obviously now VMC) they can instruct the aircraft to enter the circuit (when the MET criteria is there) if for some reason the aircraft goes round or is instructed to go around by ATC for whatever reason.
I'll investigate all the rules and talk to the man in ATS OPS (Airways policy and rules person) and get back.