Is the limit supposed to be separate from the stamina system?

Inventory space.

I mean I can simply drag ammo/items from the ground or other inventory sources into my uniform, vest, or backpack. However, the "canAdd" command returns false, and I can't use the right click "shortcut" to move items into my inventory.

That is true, however if you disable the stamina/weight system canAdd will return false. The only thing that is making it return false is stamina/weight, however since stamina is disabled, it shouldn't matter.

Essentially, "canAdd" shouldn't check for weight when stamina is disabled.

Does that clear it up?

OK, it seeems that I'm still unclear:

If you run the script I provided, your character will have the "stamina weight bar" at the bottom of the inventory menu almost completely full; HOWEVER, the player still has plenty of inventory space: the uniform is almost completely empty, and the chestrig as well as the backpack are completely empty. The player is still able to hold at least half a dozen more Navid boxes, however the "canAdd" command returns false because the stamina bar at the bottom of the inventory is almost full.

Related screenshot:
http://puu.sh/lKf69/6e9e09a48e.jpg

(screenshot is not by me)

oukej, with all due respect, I don't think you understand the issue.

Weapons such as mounted .50 cal tripods don't need to aim at weakspots. Same with GM6 Lynx APDS and such. If the AI is within reasonable combat range of a Strider/Hunter/Ifrit and is armed with a powerful weapon (at least a mounted .50 cal tripod) then they should just start shooting at the vehicle. No need to worry about weakspots.

The underlying issue is that the AI treats MRAPs the same as heavily armored vehicles. Even AI with the GM6 Lynx and APDS rounds will not shoot at the MRAPs.
The APDS rounds can disable wheeled IFV's like the Gorgon!

Even AI on mounted .50 cal guns (tripods/offroad armed) will simply not engage MRAPs. That makes no sense, because those .50 cals can more than easily dispatch an MRAP.

I really hope this is fixed by 1.52, because it makes no sense that somebody in a strider can simply run over all of the AI, even if they are all armed with LMGs/MMGs/HMGs, and Anti-Materiel rifles.

EDIT: It wasn't fixed in 1.52 (not surprised, it was reported right before the patch). If this could at least be looked at, that'd be great...

I'm not asking BIS to let us shoot out of windows; just out of open unprotected areas such as the back of a pickup or off the seats of a little bird, just as they have it in BF3.