There is no credible evidence that the Zapruder film has been altered. Another of "very few people who saw the uncut original of the film" was Abraham Zapruder, and he repeatedly said the film showed exactly what he saw that day. Furthermore, it's consistent with the Nix, Muchmore, and Hughes films. Furthermore, it's consistent with all the other physical evidence. Furthermore, neither Horne nor anyone else has ever provided a remotely plausible explanation for how such alterations could have been done in 1963 given any amount of time, much less in the brief time before copies of the film were made.
You say Brugioni "is a film expert and no huckster" and link to a 1.5-hour video which supposedly supports your contention that the "Zapruder film that the public saw was highly edited." Yet, all Brugioni says that seems pertinent to that issue is that he remembers the "pink cloud" of debris being much larger in the print he made than what he now sees in some other (unidentified and unspecified) print, and he speculates that the frame he made a print from has been removed (for some unidentified and unspecified reason). Well, I don't claim to be a film expert, but I've certainly seen different scanned versions of frame 313 where the debris cloud looks different, which I take to be simply differences in the printing or the scanning. And I can also look at the Zapruder film myself and see no evidence whatsoever of frames being removed, which would be completely obvious. (Some JFK conspiracists follow that observation to its "logical conclusion": the film was not altered; it a complete fake.) So "expert" or not, that falls far, far short of being proof of such an implausible claim.
Seriously, if you find Horne's other lame arguments in this video compelling, then I suggest that perhaps you haven't really thought them through.
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