That being said let's concentrate on what is offered here. It is abundantly clear that the very great Tebaldi is to be found in the first items on the first DVD. There the voice still has the unimpaired velvet that would somewhat disappear after her first vocal crisis in February 1963 to be supplanted with a more metallic though still clearly recognizable Tebaldian sound. The pieces from La Boheme with Bjoerling are well-known and VAI is so honest to note that the sound is a synched audio recording made in the studio during the telecast to suit the kinescope image. This is the correct procedure as picture recording was rather primitive in the fifties and often directly recorded sound (which could be more easily preserved) and images (which got blurred or sometimes even got lost for a second) don't quite match if one doesn't take this road. Luckily the synching is done expertly and once more one is struck how natural an actress Tebaldi is; surely when compared with Bjoerling's stiff attitude.
One of the surprises of the lively debates on several opera forums after she died was the remarkable opinion of many veterans who saw both ladies that she was a more believable actress than Callas who seemed to many still to be stuck in the grand guignol-style of the thirties. We don't have Callas as Cio-Cio-San but it's hardly believable she could improve on Tebaldi's magnificent interpretation of the two arias (and in full colour as well. As a bonus you get these scenes somewhat longer in black and white as well but this hardly deserves the "first release" cry). I'm wondering if the full colour "Si, mi chiamano Mimi" is still somewhere in the archives. The sound track for that item (I often saw on Flemish Public TV) is derived from her second complete Boheme as was clear from the audible "Si" by Carlo Bergonzi between the two parts of the aria. A picture of that video found its way to the cover of the London-(not the Decca) issue of the opera on LP.
The telecast of 1961 is less to recommend. The picture is somewhat murky and the soprano has to wear some things which could make an impression on the Family Circle at the Met but are very much overdressed, even ugly in close-up. The excerpts from her Stuttgart Tosca are more worthwhile, though it is not for the strangled sounds of tenor Eugene Tobin or the dry voice of George London. I remember well the excitement almost 45 years ago when the opera (followed or preceded by an Otello with the horrible Hans Beier) was broadcast by Eurovision in Western Europe. Most countries had only one channel (the big ones had two) and commercial television didn't exist. At that time opera singers were still household names and the fact that Tebaldi would sing directly was front page news. She is in good voice though somewhat husbanding her means at the start and one now notices how she cuts short her top notes.
The Concerto Italiano was recorded by Canadian Broadcasting Corporation in 1965; so just in time before the decline from 1968 onwards when her top register became completely unhinged and she refused any engagement in a complete opera performance outside the US as there alone she was sure the fans would turn in a deaf ear to her vocal shortcomings. In this broadcast she is at her best in Rossini's Regata Veneziani which she sings (and acts) with love and a dose of humour and which moreover poses no vocal hurdles as she must go no higher than high A. The long Tosca selection of the second act is less successful: not as to singing per se though the voice is steelier than in her great years but she is far more convincing, far more natural in her two complete theatre Tosca's. The cameras follow her closely and she is clearly overacting, always doing things, throwing looks, moving hands one second longer than is necessary. I fear the TV director is the culprit as there were no subtitles at that time and there was so much fear the audiences wouldn't "capture" the story; but four decades later it almost looks like a parody on Tosca. This time the soprano is more than ably partnered by the young Louis Quilico and he too has to squirm in overdrive.