Ray, as a preface, let me say that I totally agree with you, and think this series might be a big mistake on Andy's part.
That being said, Andy explained his decision like this: He wanted to find a way to make Streets of Old Hong Kong more marketable outside of Asia. He thought the U.S. Navy and Marines from the Yangtze patrols were a popular subject which tied in nicely with the Hong Kong figures and diorama facades. This, in combination with the reference to a movie Andy truly loves and believes to be very popular with collectors, made Andy believe the series would sell, especailly if he could find a way to affordably retail the boat itself.
Personally, I think Andy miscalculated on this one . . . but then again, I thought polystone vehicles were a big mistake, so obviously, I'm a moron when it comes to the Toy Soldier marketplace.