38. Tong-Il strangle

Since I've previously covered a strangle in Choong-Moo and another in Ul-Ji, here is a third one from the final pattern in the ITF system: Tong-Il. While I doubt any readers know this pattern, it's another example of a Judo strangle being used in a pattern. The set is:

• 9: L.B.S. High outward strike with right backhand
• 10: Left inward vertical kick to the right palm
• 11: Land into R.B.S. and perform a twin palm horizontal block in slow motion
• 12: Step forward into R.F.S. high side block with the right ridgehand

In the 1965 instructions, step 11 is merely directed as bring both palms horizontally in front of chest. So the movement is neither described as a block or a strike, and the palms are emphasized.

I considered that this movement might be part of a throw (pushing out with the elbows) or perhaps a downward push. But neither of those two applications match the description of the movement. Instead it may be seen as setting up a single wing choke, or kata ha jime.

Use step 9 to lift and get outside the opponent's right arm. Perform the inward kick not to your palm but to the opponent's leg (although this kick to the palm is in many patterns, it's generally thought this is for show and that the intent is a kick to the back of the knee). This shifts the opponent to your right, placing you behind them.

From here, underhook their right arm with your right arm, and reach around their left shoulder with your left arm. This puts you in the "twin palm horizontal block" position.

Place your left backhand behind the opponent's head and grab their right lapel with your right fist. (This is the chamber for the ridgehand block). As you perform the ridgehand block, you pull in the opponent's lapel while pushing out their head with your right backhand, completing the strangle.

Single wing choke. Source: wikipedia

See the pictures here for step-by-step details. Or see a video here.

Why are there strangles in the ITF patterns? Judo was a popular martial art in Korea during the Japanese occupation (native Korean arts were suppressed), and most of the original masters of taekwondo had some Judo knowledge, as evidenced by the sections on self-defense and throwing in early taekwondo manuals. Although strangles are not found in these manuals (to my knowledge), it makes sense that some of the strangles from the Judo curriculum would find their way into the patterns.

37. Choong-Jang first spin and slide back

The set is:

• 5: R.F.S. left two-finger strike
• 6: In place, R.F.S. front backfist strike
• 7: L.F.S. rising block
• 8: R.F.S. middle punch
• 9: Moving right leg, turn 360-degrees CCW and then slide backwards into R.B.S. forearm guarding block

The original set in Woo-Nam is similar, except a high punch is used and the forearm guarding block is in fixed stance. 

I emphasize the slide because it's often ignored in performances. The second spin later in the pattern has no slide. The canonical application for the slide is that you are dodging an attack, but why the spin beforehand?

Starting with the two-finger poke, we should be pulling in the opponent's left arm. Use the supporting arm of the front backfist strike to hit down on the opponent's elbow. Then you may use the strike itself as more of an uppercut to the opponent's jaw. We follow with the rising block as a quick second strike.

Source: Traditional Taekwondo Ramblings

Alternatively, you could use the rising block to raise the opponent's left arm from underneath, or to attack their outer-elbow. Whichever option you choose, grab the opponent's left arm and pull it with your left fist as you punch the opponent in the ribs with the middle punch. You could also punch the jaw (as in Woo-Nam). It doesn't really matter; what's important is that you end up outside the opponent's left arm.

Now for the spin: we use this to put the opponent into a waki gatame ("armpit hold"). By spinning into the forearm guarding block, we rotate the opponent's arm and use the back arm to place downward pressure on the back of their elbow. The front arm both twists and lifts the opponent's forearm.

Pull and punch to waki gatame. Notice how the tori steps with their right leg, although he doesn't do a full spin in this case. Source: TRITAC martial arts

Google "waki gatame" for more examples.

From here the meaning of the slide is obvious (they even talk about it in the linked video): it's a way of breaking the arm, or at least forcing the opponent to the ground to avoid their arm being broken. A more extreme version of this is to sit down on the opponent as you lean your weight backwards.