Happy to report that the cleaning went very well!
Dawn dish soap, hot water, and a toothbrush removed all the polish from the horn pretty easily, without a lot of scrubbing. The scales (especially the show side) look a good bit different now. All of the finer light-colored streaking in the grain is now gone. Overall, this looks better IMO.
Pros: No fine, light-colored streaking in the dark horn. Looks much better I think.
Cons: The polish
does fill in some of the deeper grooves, which gives the surface a nicer, smoother finish, in both feeling and look.
The show side of mine was fairly flat, and after removing the polishing compound, you can see that the actual fibers of the horn were not polished too well, so much of the glossy look is gone. The pile side was polished much better, and retains most of the glossy-looking finish without the lighter-colored streaking.
If I had my druthers, I would have preferred that Viper used a darker-colored polishing compound on the darker horn material which would have blended better. I generally prefer the smoother, glossy feeling that the scales had with the polishing compound still present. But the streaky look bothered me once I realized what was causing it. For this reason, I elected not to remove the polishing compound from the lighter colored knife I have, as the polishing compound does not distract from the look like it does on the dark one.
Here are a couple poorly-lit pictures of the results (and the as-received pics from earlier, for easy comparison). I'll get better photos tomorrow in the natural light.
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