In reply to UKH Articles:
it's a challenge devised by Philip Tranter (him of the Tranter Round) with an ugly name which I think was Scotblob, 50 members of a single club to achieve all Munros in one 24hr day. I believe the idea would have been without car travel between peaks but don't know about that. Scottish Moutaineerng Club Journal may have some reference. A mountaineering club - Lomond? Ochil? made a couple of attempts on it in 2nd half of last century. I'm fairly sure it's never been achieved. Would be good to know the minimum number of Carnethies to cover all the summits (ie if it was a pair, only need to count one) for future attempters to reduce.