Interesting points brought up by all. I am slow school...yes slow school. I distrust certain elements of technological solutions, and optics is one of them. When the Marine Corps purchased ACOGs (which became Rifle Combat Optics - RCOs duing full procurement), I noticed a few things.
The first is that an RCO doesn't necessarily make everyone a crack shot. If the shooter sucks at the fundamentals of marksmanship, the RCO may only show them how much they suck between strings. I am a firm believer that if you cannot go 10 for 10 with a properly zeroed M-16 at 500 yds, in the prone, you are not applying the fundamentals consistently.
At the end of the day, it will always come down to the basics, a stable platform, and muscle memory. Too many problems I see in inexperienced shooters come from a failure to consistently mount the weapon into the shoulder, or a sloppy shooting position that screws up natural point of aim. Despite having had excellent instruction in bootcamp, when I advise a shooter that they need to check their natural point of aim, they do all sorts of weird stuff and not what they need to do.
I've never shot an M-16 series weapon with any sort of optic, so the jury is out still on whether I like them. The funny thing is that too many Marines will want one for the "cool guy" factor, and not read the instructions, as mentioned before, nor do they try to understand the theory behind the scope.
About twice a year, I re-read The Art of the Rifle by Col Jeff Cooper. It is a easy read, yet full of tips and concepts that I think every student of marksmanship should own.
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