You completely missed the point of the game didn't you.
Nobody ever claimed Silent Scope was meant to simulate being a police marksman did they?
It's a rhythm game (so yes it requires hand eye coordination) with a guitar shaped controller. That's it.
If you play guitar you should have the pluck+fret action down (which people can find hard when learning either GH or guitar), and your pinky will be more adept at blue and orange than mine, but if you can't follow the rhythm game convention of hit the shape when it touches the line, then you're going to suck.
It's more like playing scored air-guitar than anything else, you get to strum along with songs most people could never play and when you perfectly hit the solo, or the song hits a crescendo it feels good.
Rock band multiplies this up by making it a group experience.
What you could do (just had this idea), is produce a USB A/D converter which takes a guitar phono plug and have this produce on the fly midi tracks which are compared in the background to pre-recorded midi track sync'd to the original mp3 which you can hear. Then you could play Real Guitar Hero.
Well if you'll excuse me I have to go write a review of Track and Field where I complain that as an Olympic runner I expected to be better at it...