A long time ago (before the 1950s or so), sport fencing was performed by two competitors who faced off before a jury of five judges, whose job it was to determine who hit whom, when, where, how the hit was accomplished, and which combatant should win the touch. This system rewarded fencers who had flawless, classical style, so that the judges could see precisely what the fencers were trying to do, which of course made it much easier for them to determine correctly if the fencers had successfully done whatever it was they were trying to do. The first part of many early sport fencing tournaments was for each hopeful participant to demonstrate his fencing form before a panel of judges, so that the panel could select the cleanest and prettiest fencers for the competition, which made the job of judging much easier. The principal drawback of this system was that winning a touch still depended upon the judges seeing it, which of course never seems to happen at critical moments in the fencing bout.
The solution to this was to introduce the electric scoring system, in which both fencers are hooked up to wires leading from their weapons back to a scoring machine, which has lights and buzzers that go off when a fencer hits his opponent. The principal advantage of this system is that hits are judged by an impartial machine without any vision problems. The disadvantage is that the equipment tends to fail, which of course always seems to happen at critical moments in the fencing bout. Electric scoring was introduced first for épée, not long thereafter for foil, and several decades later, for saber1. It's important to note that there still is one judge in electrically-scored fencing bouts2, but the amount of human judgment needed to award any given touch is far less than with non-electric, or 'dry' fencing. The electric scoring system indicates, more or less reliably, which fencer(s) hit on a given action, but the remaining human judge still determines which fencer gets the touch.
The introduction of electric equipment had another, unforeseen effect upon the dynamics of fencing, especially in foil. No longer did a fencer have to be 'pretty' to score a hit. All the scoring machine knew is if and when the tip depressed on the opponent's target. This fact led inexorably to new and sundry techniques for landing a touch, many of which have absolutely no analogue in an actual duel with real, sharp, swords. Nevertheless, if a fencer can legally employ a strategy to hit his opponent without getting hit in return, one can be sure he will adopt it as soon as he finds it. The most notable new foil technique developed since the introduction of the electric scoring system is known as 'the flick'.
A fencer who wishes to score a touch using the flick typically begins extending his weapon arm towards his opponent, as if he were about to fully extend it and finish the attack with a straight thrust. Many opponents will attempt to time the thrust so that they can parry it - that is, block the attack with their foils. The attacking fencer, however, never makes the straight thrust. Instead, he closes distance on his hapless opponent, makes a whipping motion with his sword hand, somewhat like the motion of a fly fisherman casting his line, which causes his foil blade to double over on itself such that the tip actually points back towards him for an instant. If this is timed perfectly, it is possible to hit an opponent on the back with what began as a straight thrust.
A good proportion, maybe as many as half, of touches in high-skill level foil bouts nowadays are scored with this move. Fencing used to be an art of two experienced fencing masters, each with perfect classical form, thrusting and parrying, looking for openings and trying to outwit each other. Now, mostly due to the rise of the flick and the simultaneous liberalisation of rules defining what constitutes an attack, it has become a sport of two young athletes looking for an opening before the blades are ever engaged, then hitting one another on the back with perfectly-timed flicks. This has made the sport more athletically demanding, and much harder for the uninitiated to watch. Essentially, fencing has evolved from the practice of preparing noblemen for fighting in duels, to a sport which, some would argue, has little to do with fighting in real duels.
There is rather a lot of debate about whether this evolution is good or bad for sport fencing. There are essentially two camps. The first maintains that the flick is a travesty that has pulled fencing away from its roots and destroyed the artistry of the game. The second holds that the flick is a nifty move that has pulled fencing away from its roots and made it into a real sport. A good analogue to this debate can be seen among fans of basketball, about which some say that the introduction of the slam dunk has ruined the game, and that none of the players can consistently make foul shots anymore. Note that most basketball fans love the slam dunk. There hasn't been much study on if the corresponding, er, um, legions of fencing fans love the flick.
Defending Against the Flick
There are at least three ways to avoid being hit by a flick. Three are presented here, in approximate order of preference:
Time your opponent's attempt to flick, and then change the distance very quickly and suddenly when it starts. Displace your target, or close in precipitously with a counter-attack. If you time this action just right, it makes it extraordinarily difficult for your opponent to land his touch, while you have an easy job with your counter-attack.
If all else fails, try to make a perfectly-timed parry in quinte5 or circle-four to catch your opponent's blade. This is hard to do.
Learning How to Flick
There is an intermediate level of foil fencing at which many fencers attempt to learn this move. Their team mates, coaches, and opponents will thank them if they bother to learn it quickly and correctly, instead of going through a long phase of whipping opponents on the shoulder with the flat of the blade in an attempt to flick, causing numerous bruises and lost tempers.
First of all, you should learn the basics before you even try this move. Fencers whose only decent move is the flick tend not to be very good. They can beat bad fencers who don't know how to defend against the flick, but they can't beat good fencers. So, have other tricks in your bag before you attempt to acquire this one. You also will need to be fairly adept at manipulating the distance between yourself and your opponent in bouts, as distance and timing are critical to successfully landing a flick. Basically, if you haven't been practising with a blade for at least a couple of years, you probably shouldn't try this yet.
The motion with the hand should feel a bit like casting a fishing line. Pick a stationary target (a wall target, a pile of mats of the right height, etc), and practise it. Try to land your hit lightly - enough to depress the tip, but not any harder than necessary to depress it consistently.
Once you have this motion down, pick a partner and follow the following drill. We'll assume both fencers are right-handed here, for simplicity.
Your partner extends in your four-line - that's the high, inside line, to the left of your blade if you're right-handed.
You execute a 'flying parry'6.
Now, carefully lower your point, using your fingers and hand, angulating to hit your opponent on his right shoulder.
Do this until you get it down.
Now, it's a simple matter of speeding this drill up until your riposte with angulation turns into a flick without your having to think about it that much.
Once you've learned it, you may find that the flick essentially substitutes for another finishing line. Good opponents will be able to figure out quickly if you always finish in a given line. If you have mastered enough moves to establish legitimate threats in two or three lines, it will be much harder for your adversaries to parry you. For this reason, it's important to remember that the flick is no magic bullet. It's not the attack to end all attacks. If a skilled opponent knows you're going to finish an attack with a flick to a certain line, it's actually pretty easy for him to parry you. There's still a mental chess game to be played when you fence, and even though the rules and the 'look' of the sport have evolved over the years, there are some guiding principles which have been true for as long as humans have fenced for sport. One of them is that if your opponent can guess what you're going to do, it becomes quite a lot more difficult for you to do it. Keep that in mind as you fence.