There is still no substitute for proper training, task orientation, correct attitude and vigilance. If you look sharp enough you will see the holes in the cheese lining up. I've made my fair shares of mistakes and both attitude and vigilance (or lack thereof) took part in all of them. I hope that I'm wiser now...
At last - some reality.
Despite protestations by the perfect pilots of pprune we ALL make mistakes because we are human. I made some real doozies in my day but I learned from them. Picking up on your own errors takes vigilance and a finely tuned suspicion of that feeling that something is not quite right.
Assume nothing, check everything and then check again.
The second pilot is there for good reasons and one of the most important reasons is to monitor the PF. Two heads are better than one.
I often wonder how many of todays perfect pilots would have survived a ten year stint as a single pilot in the african bush. Fortunately the Twotter is a very forgiving big old pussycat..........