I noticed that while duel wielding in halo 3 campaign, if you press reload only the weapon in your left hand will reload, the right handed weapon will only reload when its magazine is empty, not sure if this was in the original game, but I noticed it while playing today.
Not in original game definitely need to fix that 343
Dual wielding is also giving me issues in Matchmaking, occasionally my character won’t bring the right weapon back onto the screen.