Marcos
I believe there has been chat about it off and on for years and I know that Ken Moodie did a nine hole design for them back in the 1990’s (I think). Given the subsequent land swap with Renaissance they may have shelved or given up on the idea but then again maybe not. Either way, additional holes at the other side of the property would be a long way away from the clubhouse, and I doubt that the club would sanction a complete re-routing of their existing course to make the start for any additional holes closer to the clubhouse. I also can’t imagine them bringing in a fleet of buggies to get people over to the new holes.
As for lady members, from what I’ve heard most of the single sex clubs that voted in women members did so in the expectation that they wouldn’t have to accommodate that many. That seems to have been borne out, at least for the moment.
As it is I doubt Muirfield is all that heavily played such that it would need a relief course to take some of the pressure off. Maybe a new shorter/easier course would suit some of the old boys but again, the land for the new holes is a long way away from where they dispense the kummel.
Niall