Great videos, chaps. And thanks for clearing up the mystery of the Rooftop Singers' TV appearance. I wasn't sure that Australia even had a television service quite that early.
One essential addition to the UK history of the 12-string guitar is to mention the cottage-industry that was guitar-builder Stan Francis, in Liverpool. Stan isn't tremendously well-known today and neither are the jumbo-type guitars he used to build, but his 12-string models were literally renowned among world-famous among folkies. Pete Seeger, Tom Springfield, Mick Groves (of The Spinners) and most relevant on a Shadows fan board: Lonnie Donegan, used his 12-string models and many other famous folk-scene alumni used his services for set-ups and repairs. I played in a country band whose lead vocalist played a Stan Francis six-string model, though these never achieved the adulation that the twelves did. The design was very distinctive, with a D-shaped soundhole and a round aluminium headstock anchor for the truss rod.
Stan may not have been world-famous, but he was very respected among the cognoscenti. Almost unbelievably, CF Martin and Co have recently announced a Peter Seeger tribute model based clearly on the Stan Francis design:
http://www.musicradar.com/news/guitars/namm-2011-martin-guitar-announces-pete-seeger-custom-editions-359014
Also:
http://www.acousticguitarforum.com/forums/showthread.php?t=144580
http://www.thebumnoteclub.com/reports/8-general-reports/103-martin-carthy.html
http://www.triumphpc.com/mersey-beat/archives/scousers-chorus.shtml
http://www.mudcat.org/thread.cfm?threadid=60884
http://www.folkmusic.com/gear/12-string-guitar
From the late 1950s onward - and for a long time- Stan was probably the only person in Europe building professional quality 12-string guitars.
JN