Well The Mephisto Waltz is coming out on Blu-Ray in the UK in 2017. Wouldn't it be nice if they dusted off and remastered the film of that recording session.
Well, technically speaking, it would be impossible to remaster interlaced PAL video in HD (it would be akin to trying to remaster mono into stereo).
However, I agree it would be nice if the original video masters were transferred digitally and made available for viewing -- assuming they weren't bulk erased (which sadly wouldn't surprise me -- look what the BBC did with all those old Doctor Who episodes).
In those days of the filmharmonic, Bbc tv used to screen a highlights show - probably where that 1975 clip came from. I do recall one year around that time the Goldsmith sequence included Patton and footage from the film of george c scott riding in his half track. A more knowledgeable goldsmith fan would know when this was coz Jerry was on a few times.
Some lovely stuff there, especially Last Run and Wild Rovers.