I think Snaking Talon is an excellent example of a lot that is right about American Kenpo, and also a lot that is wrong.
The way I was taught this technique differs significantly from the way I believe many other AK schools teach it, but I think both variations have similar weaknesses.
In the technique as I was taught it, the attack is a right step thru punch left cross punch combo from 12.
The defense is a figure eight parry with the right hand while checking with the left beneath the parries at solar plexus height while stepping back with the left foot and then drawing the right back into a right cat stance. After the second parry, execute a right counter grab to the opponents right wrist and pull him slightly forward as you execute a right front thrust kick to the opponents bladder. Simultaneously land the right foot back towards 7:30 in a left rear twist stance as you execute a right arm whip to draw your opponent's head down into a left upward foot palm. Execute a right rear chicken kick to the opponents solar plexus at an upward angle to create space and spin out towards 6 oclock.
I post the technique as I was taught it so that I can address some of the issues I have with both this version, and what I believe to be the more common version as found on the Kenponet written curriculum, which I will refer to as the EPAK version. Simply referring to a technique is insufficient to discuss it when so many of us practice personalized variations of the root.
In the EPAK version, the attack is a high two handed push. While I like the dimensional checking of the handsword strikes to the opponent's arms, in combat a high two handed push is executed in one of two ways, neither of which lends itself to this defense.
If the push occurs during the "escalation phase," it will be with the opponent's arms mostly extended towards you and the push will be with the hands, intending, at least subconsciously, to gauge your commitment to battle and physical preparedness. If it is during the combat phase, you will face the loaded high two handed push where the opponent cocks his arms towards his body, and steps towards you with a committed push meant to create space or push you down.
If it's the first, the handsword strikes will be far too slow to do more than wave away his arms after he has already pushed you, making you seem reactionary and slow, encouraging your opponent. If it's the second, the handsword will strike the left arm, creating the dimensional check you are looking for, but also diverting the second push in such a manner as too make the second handsword strike improbable at best.
Consider the technique Triggered Salute. When your opponent pushes your body with one arm, you swing towards him by pivoting over your center to add force to your strike. When you strike the outside of his left arm, you will cause his body to pivot around that center in the same way. This happens because in order to effectively execute the committed two hand step thru push, the opponent engages the muscles in the entire arm, creating a solid structure between his arms, shoulders, and chest. To some degree, this dimensional checking is the point, but it negates the effectiveness of the second strike.
Think about Aggressive Twins. You block one arm and your opponents body is turned at an angle. It is the dimensional check which defends against the second arm. You can't reach it, you can't attack it, but it can't attack you either. That's the point.
In the variation that I was taught, the attack is, I believe, more appropriate to the defense. Usually we think of techniques in the opposite sense, is the defense appropriate to the attack, but here I think this is an important point.
Both types of attack are common, realistic, combat scenarios. Pushes are extremely common intentionally and otherwise, and the kind of right left punch combination is as well. In fact, I prefer to think of the attack as a right left stalking combination, where I am retreating from my attacker as he pursues me with repeated punches. If you doubt the effectiveness of such an attack, youtube some of Tank Abbot's early fights.
However, this defense, in either variation, the parries or the handswords, requires that you react to your attacker and pursue strikes he's already thrown crossing your center line twice from the outside of the body in an elongated circular motion. This is unlikely bordering on impossible with an extended arm push and difficult even with a loaded two arm push. You are not going to catch up to two straight strikes thrown simultaneously with a circular motion that begins from the opposite side of your body.
On the other hand, with a two punch combination you have a built in delay between the two strikes, and following your defense of the first, you are in position to defend against the second. The reason your opponent's second attack isn't disrupted like it is with the push scenario is because your using parries instead of strikes, which create less angular disruption, and your opponent is striking successively, not simultaneously.
The follow up front kick is pretty standard. As always, I emphasize striking the bladder instead of the groin because I find it to be a sharper pain, and a more effective target for body manipulation. Of course getting struck in the testicles hurts, but it is a dull emanating pain, while I find bladder strikes to be sharp and intense. More important than the pain however, which I find to be unreliable at best, is the body manipulation that bladder strikes afford you which groin strikes do not. By striking the bladder, especially with a thrusting strike, I am able to pivot my opponent over the hip girdle. Doing this with groin strikes is difficult and often more a result of your opponent hunching over in an instinctual defense of the reproductive organs, or in response to the pain.
The remainder of the technique is, at best, inefficient. Using either variation of this technique, why, when your opponent is checked, grabbed, and doubled over, following a kick to his midsection, would you choose to land in a twist stance and turn your back on him? Why would you choose to use a less mobile, less stable stance while connected to an opponent, especially one who has possible internal injuries following the kick? Certainly you kicked him with the intention to cause some injury, yes? Why would you choose to cross your own center line, again, in the direction of the arm you have turned away from your body? Why wouldn't you move towards your opponents back instead? Why would you choose to execute a dangerous combination of kicks, while still holding your opponent by the arm? I was taught that there are two ways to get hurt by an opponent, intentionally and unintentionally. Even assuming my opponent has no intention to fight back, what if he falls down from my strikes while I'm on one foot in a twist stance and holding his arm?
Most importantly, why didn't I simply follow my front kick with strikes to my opponents head, neck, and back, followed by a a two handed grab to the back of my opponent's shoulders and a dragdown of my opponent towards 8 oclock? Why dance? I understand that circumstances may force me to land awkwardly, or back, even in a twist, but why in the ideal phase of this technique do I choose that option? It seems it is simply to justify the chicken rear kick, which is not a good enough reason for me. I believe in chicken kicks, although not rear ones. The point of a rear kick is that you are engaging some of the largest muscle groups in the entire body in the lower back, buttocks, and legs. Why surrender this advantage by kicking in the air instead of leveraging against the ground? I've used front chicken kicks in pursuit of a retreating enemy. Used properly, they are a viable weapon, but this is not the time or the place.
There is good and bad in this technique. The defensive maneuver here, in either variation, is an effective technique. I've used the parries in combat. I've used the handsword blocks, although not successively against a simultaneous attack as proscribed. Both are effective defensive maneuvers. But like too many of our techniques, a solid defensive maneuver is followed by an unnecessary counter striking combination. It isn't that front kicks, and rear kicks, and even twist stances, aren't useful and effective. It's that this sequence of them doesn't best address the problem at hand.
-Rob
As for this particular kick, I suggest breaking it down. Execute a back kick. After the kick, return your leg to a chambered position. Then work on hopping onto that leg, as you bring your other leg into the chamber position. After you've done this for a while, once you do the hop, just throw the kick with the other leg. 
