So, I am confused. Help me out here. You are using a fictional movie character and a single published source as the basis for the assumptions you are presenting? Just to provide some basis for my following comments....in researching Corregidor I used more than twenty five published sources including "official" ones. I also used almost twenty online sources in gathering research data to justify my decisions and I had access to many sources in the Philippines not available to non-Filipinos due to having relatives living there. Those all gave me a good solid base to work from.
The 4th Marine Regiment (China Marines) was an exceptional force with a good deal of fighting experience. The crews of the naval gunboats could fire small arms, but they were naval personnel. They had no formal training in ground combat. They proved resourceful and aggressive in ground combat on Corregidor but they did so in very small unit actions.....seldom more than one or two squads in size. They knew nothing about larger unit maneuver or coordinating attacks with other units. If the 1942 battle on Corregidor had lasted, say, a couple of weeks, the deficiencies inherent with the Naval Battalion would have been revealed repeatedly and their general weakness in ground combat exploited by more experienced and better trained enemy forces. When the Japanese made their big push on Corregidor, they hit the section of the line partly held by the Naval Battalion and Filipino volunteers. They were overwhelmed and many broke and ran to the rear. Not exactly a stalwart ground unit.
Perhaps a case could be made for using 347's instead of 447's for these naval units. Since MMP did not issue any US 347 counters, and to help limit costs, we went with what was available already in the system.....and the grand tome does state that the 447's represent early war US forces. Simply adjusted the number of MMC used to balance the scenario using the Naval units. Playtesting validated my decisions.
Not really criticizing your views. I just wondered why you felt that a movie and one source was valid,, or enough, to support what you presented? Even using several sources I found conflicting data, possibly skewed by the author's bias or lack of in depth research. Happens all the time. That is why I always try to get multiple sources to achieve a "consensus" view, and work from that. If anyone questions my assumptions I can back it up by saying " I used such and such as sources for this". The more sources, the better. Good discussion.