Greetings, everyone. I decided for the time being to turn my test map into a testing grounds for what the object count actually is, and what the poly count actually is, and whether and why this changes depending on the objects used, or the computer used. My first test is complete:
On my lower-end computer, I used a bunch of simple box props (six sided, so even if the collision makes the poly count double and it's triangles and not quads (not sure, I made the prop a while ago) the maximum number of polys for the prop should be 24) and tested various amounts to find the object limit as opposed to the poly limit. I found a limit, yes, and on my computer, anyway, it always made it lock up at the end of loading, rather than crashing to desktop. When I tested with roughly 1300 objects or more (in addition to some vehicles, 16 cps, and 32 troops) it froze up, but with slightly under 1200 it did not. If in fact that's 24 polys each, that would be only 28800 polys, which I believe is well under the poly limit. I will test this in the future by substituting both simpler and higher-poly models with the current box model.

Hmm, interesting. What about a smaller number of higher-poly props?

A couple of things to add to your thoughts:
forums/viewtopic.php?p=437511#p437511
forums/viewtopic.php?p=438294#p438294

Both are in a WIP thread of mine and at least refer to issues I was having with undocumented crashes due to (perceived) tri limits. I didn't do much hard testing, because my goal was to make the map work and not to necessarily gather data (so anything is only anecdotal and could simply be wrong), but there you are.

I substituted the simple props for ones with more polys, and the map still didn't crash, so I think from that we can determine that I was in fact hitting the object limit as opposed to the poly limit at around 1200 objects. Worth noting is that while with the box prop at the object limit there was little to no lag and no disappearing objects, with the higher poly objects there were disappearing objects and some lag. Next up, trying to find the poly limit. It seems this is what people are more likely to hit, since I'm pretty sure I've reached it with well under 1000 objects on my one map mappack map. And, in hypothetical theory, hitting the poly limit makes the game crash to desktop rather than freezing up, making it possible to tell which of the two limits you have hit.