I was nosing around in the game's .iwd files looking for a specific image, when I stumbled across a few others by accident, which reveal some interesting things.
Original file name: hud_weaponmode_semi.iwi
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Original file name: hud_weaponmode_full.iwi
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So I guess originally we were supposed to be able to switch between semi-auto and full-auto, but for some reason IW decided to leave that ability out of the final game.
Original file name: hud_temperature_gauge.iwi
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Apparently an overheat gauge was developed for the mounted MGs but didn't make it to the release.
I really think that these things should have made it into the game. Overheating would stop the gay mounted MG spammers (read: Downpour). Fire modes would be nice, but I don't think they are as important as overheating.
Original file name: hud_weaponmode_semi.iwi

Original file name: hud_weaponmode_full.iwi

So I guess originally we were supposed to be able to switch between semi-auto and full-auto, but for some reason IW decided to leave that ability out of the final game.
Original file name: hud_temperature_gauge.iwi

Apparently an overheat gauge was developed for the mounted MGs but didn't make it to the release.
I really think that these things should have made it into the game. Overheating would stop the gay mounted MG spammers (read: Downpour). Fire modes would be nice, but I don't think they are as important as overheating.