The best way to help it bomb is to turn it into a joke that people will be embarrassed to admit to liking.
To do that, we have to know enough about the movie to hit the target.
Right you are. More years ago than I care to admit, I studied Astrology, precisely for that reason, so I could authoritatively ridicule it. I was in a bookstore (Barnes etc.) somewhere in Manhattan, browsing the subject when I picked up a book entitled, “The Textbook of Astrology”. I opened it up and the words were upside down so I realized that the dust cover was on backwards. I took it off to put it on the right way, and saw that the book COVER was on BACKWARDS! I bought it immediately. Great book. Just what I needed.
As for the Four Feathers, there are many versions of the film. I recommend that you start with the 1939 version, then there are at least 2 others, both good, in 1978, and 2002. The story varies little but the battle sequences are fabulous in all (IIRC).
If you’re into film let me know, we’ll talk some time.