Yes, crosshairs would be a real pain, but I doubt the devs would include any chrosshair
But the picture above explains the "shouldering" pretty well. Imagine the left soldier holding his weapon like that, just the butt against his shoulders and maybe slowly walking. At that height of the gun could lower his "cone of fire" compared to "hip-shooting" but keep a rather good intuitive aim or quick chance to use the IS. (Don't misunderstand me, I dont think there is or want a cone of fire in Red Orchestra.)
Ingame you could implent it rather easily:
Right now you try to stay in IS and wobble around when using IS while walking/trying to move. My personal experience always told me that using this in close quarter combat is nearly worthless (at least in the mod) and it feels very unnatural too - nobody would walk around while trying to focus the IS like that, since you can hardly move and your field of view is very small. But at medium too long distances you always have the time to take an aimed shot - otherwise its useless to shoot anyway.
Instead you should automatically lower the weapon a bit, looking over the IS, but keeping it shouldered, so its steadily points near the center of your screen, but not as effective as IS.
Like that it could be used as good compromise of hip-shooting and using iron sights. I think hip-shooting would become rarer too.
Has anyone seen some special forces (GSG9 in germany, SEALs or anything like that). When approching a room or so, they walk quickly while having the gun shouldered.
(I hope all this havent been said before, didnt read the thread yet

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/Edit:
Oh, and it would make pistols as sidearm a lot more effective. With the current system I often prefered the Bolt-Rifle too the pistol even in close quarter combat in the mod.