We talked about using a sight view rather than the crosshair but in the end opted against it.
I've been shooting since I was about 8, have recieved military training over the past 15 years, and have shot Cowboy competition shooting for the past 4 years and I just haven't seen anything in a game yet that does a good of replicating a realistic site picture when you take into effect the whole enviroment. America's Army comes pretty close but the problem there is lack of peripheral vision.
In real life you can easily look away from the sights for a second as you move and you can point shoot down the barrel real fast if something pops up unexpectedly close by if you don't have time to get back on the sights. Both of those things are hard to replicate in game IMO and I argued against trying. I think it's the lack of proper depth perception to some degree and a limit in the control interface (keyboard and mouse) to make you're reactions fluid enough to realistically mimic reality.
The crosshair is an unrealistic compromise but I think it mnakes games more playable and less frustrating. Opinions vary obviously but that's mine. In the end you're still sitting down at a desk behind a computer and pawing at your mouse and not actually handling a sawed off double while ambling through the streets of San Pedro with the dust blowing grit into your teeth and the sun in your eyes so it's never going to be quite the same
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