Right, that's enough - no more! This thread has got nothing to do with running and it should be banned forthwith.
But it is interesting and I'm sure that such "social" events albeit in a subterranean medium, can only be good for bonding and could even be of practical use should one fall into a hole when out running.
Please if there is sufficient support for another similar event, I would like to be included (and I know Andrew A. would too).