Driving Privileges

Disclaimer: this is not directed to any specific person, gender, age group, etc. These are just my general observations and are not meant to offend =)
It's a hot topic and for some, it's a sensitive issue.  At what point should we test our driving and determine what privileges we should have?  Sometimes, I agree that at a certain age over 70 (I think) the driver's test need be retaken. 
Then there are days like today when I swear my car is invisible. I'm cut off, almost side-swiped, tail gated, the list goes on and on.  Then I see people like this silly girl who crossed me while I sat in the median.  I wanted to go straight, she wanted to turn left.  Maybe I don't understand the driving rules, but I thought if she was going to go around me to turn left she should have stayed on the driver's side of my car.  She definitely did not do this.  She CROSSED in front of me and came in on the right side of my car.
I have determined that your driving ability pretty much has nothing to do with anything.  You're either a good driver or you aren't.  I don't know that if you're a bad driver, you can get better??  I don't know if it's a focus issue or skills issue or intelligence issue...sometimes I swear it's just a lack of thinking issue. 
If you cut me off and I honk at you, don't flip me off.  It's not my fault that you changed lanes at an intersection and didn't see me or you pulled out in front of me while I'm traveling at 45 mph and you don't feel the need to accelerate more than 15 feet per minute, causing me to slam on my brakes. Come to think of it, it would be funny if your brakes were wired to your horn. =)  What's with the horn anyhow? I know it's to get the person's attention but what if you aren't going to be able to stop, is it to let them know "hey guy, I'm gonna hit you!" so they aren't just blind sided by the impact?
Then you have little issues, like driving too slowly when you're on the phone.  If you lack the capacity to drive a safe speed while on the phone, don't be on the phone.  You will cause everyone less headache and you won't be getting beeped at. 
Then you have forgetful vehicle issues like you didn't screw your gas cap back and on and now it's flapping on the side of your car as you drive down the road.  And don't you look at me like I'm out of my mind when I tell you about it, I don't care how ridiculous my gas cap miming is! ;)
Our attention spans are apparently that of a gnat - we can't even remember that a moment ago we turned our blinker on.  Seriously??  You have a light and noise to remind you...do you not look at your dash often? I look at mine a lot but I'm checking engine temp, fuel, speed, checking to see if any random light has come on, etc.
Sometimes I think we need to install cameras in different areas of our cars and when you're honked at or have to slam on your brakes, a video is instantly emailed to you so you can see what happened, who was in the wrong, and whether or not you were making good decisions. Just a thought.
I know it's a little crazy out there; and yes, there are lots of other vehicles, pedestrians, etc, and if you are like me and easily distracted, it's hard some days with everything going on.  Just take a breath and 'keep swimming' (*Movie reference for those still with me)
I'm just sayin'.  Thoughts?

PS: This is actually the kind of thought process that makes its way through my head.  Notice I was ready to segue into a happy little Disney movie??  Yes, this is my world -- "all are welcome. and Steve's wearin' a toque"  <-- note: probably only one or two people will understand that. Don't feel bad =)