I was driving a nail the other day and managed to smash a bit of the fleshy part of a finger. As I watched it turn red, then blue and finally black, I reflected on how simple driving a nail is and yet how terribly complex the entire operation can be. OK, swinging the hammer is as simple as is hitting the nail (at least for others), but the concentration of force that occurs is anything but simple. As the broad hammer head meets the nail head, the weight of the hammer and the force of the blow are transferred to the point of the nail. As it moves down into the wood, it splits fibers, moving them aside until the force has dissipated and movement stops, waiting for the next blow of the hammer.
Of course depending on where in the piece of wood you are aiming the nail and what kind and thickness of wood you are aiming at, splitting may not be such a great idea. Years ago, I read that the key in placing a nail successfully without splitting the wood too much was to dull the point. The flattened end now crushes wood fibers instead of possibly splitting the grain. A light tap of the hammer to the nail tip is usually enough.
I tried the technique and have used it ever since. Like so many things in the shop or life, what we learn from others can seem to be a little thing but can make a big difference in our success at what we are doing.