Great, keep them coming! Didn't know they had done that to Dirty Harry. So have the original mix been absent since the LD format?
Raiders and Blade Runner were treated right in the audio department as far as I know, not that familiar with the mix on CE3K, some info from Michael Thau regarding the audio on the 2000 restoration of Superman:
Going back to the original mix, we were shocked when we heard it. We grabbed the original 70mm full-coat that actually had the label from the Pinewood stage on it; it had a date of November 1978. We put it up in a dubbing stage. We had Dolby down there a couple times verifying that the set up on the Dolby units, the decoding, was correct. Superman was the first film that was originally recorded in a 70mm 6-track split surround but here's the rub that no one knows about but it's the truth. They mixed in split surrounds but they did not use the surrounds very much, especially in a stereo way because it was very new and they were very scared of it. At the last second, here in America, they brought it over to do some final mastering on the 70mm and they chickened out and the film was only released with mono surround in the 70mm format. So they mixed it for stereo surround, but it was never released that way and the fact is that there wasn't much difference anyway.
In 1978, Dolby was just beginning to become prominent and on their recording dubber they could put a 6-track head up, a 4-track head up, a 3-track head or a 1-track. The 4-track would be for the standard Dolby mix: left, center, right, surround and the Dolby system had an crossover, where anything below a certain frequency would go to a subwoofer. The 6-track would be the same except they would have two added channels of baby-boom (low frequency bass) with more volume. The 3-track would be for the mono stems: dialog, music and effects, and the single-track would be for the mono mix. But they didn't have three recorders; they only had one at the time, the same here in the U.S. as well. So they could not record simultaneous 4-track dialog, music and sound effects stems (left, center, right, and surround.) You do a whole mix, and then you do another mix. They recorded first, the 6-track mix, then the four, then the mono mix, then the mono stems. They tried to make them one after another so they would sound the same. There really isn't much of a difference in the 6-track or 4, except in volume and bass. But you weren't preserving your stereo stems at that point. So, what came off the stage was the full mix or mono stems, which is one reason why we couldn't even reconstruct anything. We only had the mono stems. With dialog it doesn't really matter that much because you normally put the dialog down in the center channel anyway. Superman was different; they actually draped it across the whole front three speakers, which really prevented us from using any of the original mix. It doesn't work that well and sounds strange. Stereo was kind of a new gadget and I think they were just playing with the new toy. Dialog is best kept in the center channel for clarity.