I'd like to see a rider who can see an 1/32" diameter nail in the road while traveling at 60 mph... That is like telling someone that the only reason that they got into an accident is because they were not paying enough attention while driving. I'm too busy watching the retard pull out in front of me. Too busy watching the edge of the woods for deer/dogs. Too busy watching what is going on ahead of me to pay attention to what is 10 feet in front of me at 60 mph.
Within 10 feet even the great "mootavic" couldn't avoid it at 60mph. If your going 60mph, which is 88 feet per second, and see the black nail on the black asphalt at 20 feet away. You would only have about 0.15 of a second to react and avoid. Normal reaction time is 0.6-1.0 second for the average person, but the great mootavic is such a supior human being, I will assume 0.2 second reaction time, which by the way is 2x faster than the average person can blink. BUT WAIT!!! Even if your brain is processing information at a super human speed, you still wouldn't be able to avoid it.
So to tell someone to pay more attention and they wouldn't ever get a flat tire from a nail is absurd!
According to your own statement, your "mate" gus is a complete idiot for getting a flat from a screwdriver, which by the way is about 4 times longer and the handle is usually 1 1/2" in diameter and usually painted ANY color but black. The fact that it fell off the truck in front of him makes it even worse! Why was he following so close as not to be able to avoid it?
It boils down to stuff happens and you can not avoid some objects. So before you pass judgement on my motoring skill level, you might wanna rethink your own skill level. People surround themselves with others of the same basic type. If your friend drives like you suggested, then chances are so do you. So take your own advice.
MAY MORE ATTENTION AND YOU WONT RUN OVER ANYTHING AND NEVER HAVE AN ACCIDENT!