For those interested archive.org has a much higher quality version of the recording [1] as well as a recording of the 1969 followup demo that explains in greater detail how the text editor works [2].

I really wish we could try NLS/Augment on an emulator but sadly it seems that it has been doomed by the god of copyright to forever rot in the archives of the Computer Museum.

[1] https://archive.org/details/XD300-23_68HighlightsAResearchCn... [2] https://archive.org/details/XD301_69ASISconfPres_Reel1