Yul Gok
Yul Gok contains many movements mostly found throughout Pinan/Heian Yondan.
The following videos were used as reference:
ITF Legacy performance of Yul Gok.
Hirokazu Kanazawa performing Heian Yondan and Sochin (Shotokan).
Hidetoshi Nakahashi performing Pinan Yondan (Shito Ryu).
Neil Pottinger performing Pinan Yondan (Wado Ryu).
The opening sequence of Yul Gok is interesting. It is similar to the opening of Hwa Rang, though performed with a closed fist rather than open palm. The open palm variation is found frequently throughout the original kata, but I've only encountered the closed fist variation late into the pattern Sochin (seen 1:12 in the video linked above). The fist is probably coincidental, and was most likely inspired by Passai-Dai (see notes on Hwa Rang).
In Yul Gok, the first is not performed as a punch, but as an extension. Some schools perform the opening movement of Yul Gok in slow motion in the same manner as the sequence in Sochin. The following punches are at normal speed.
Yul Gok follows with another sequence found later in Yondan:
-turn 45 degrees, inner forearm block
-kick
-two punches
-repeat on the other 45
In Shotokan, this sequence is done with a wedging block (and appeared as such in Do San). Other styles perform it the same as Yul Gok, though from the other direction.
Yul Gok follows these with two hooking blocks and a punch. Choi's condensed Taekwon-Do Encyclopedia describes movement 15 as "a middle hooking block to D with the right palm." His 1965 book, however, describes a "(high section) hooking block with the (right) knife-hand."
This supported an initial theory I had regarding Yul Gok's relationship with Pinan/Heian Yondan. Most styles will end Yondan with two knife hands. Wado Ryu, however, ends with a block called "Kake Uke," commonly translated as "hooking block." Kake Uke is pictured below (right) with the ITF Encyclopedia's hooking block with the palm (left).
These blocks serve the same function, but Yul Gok's block is shown with the palm facing down. If one was to perform this block with the knife-hand, as per 1965, perhaps it would more closely resemble Wado's Pinan Yondan variation. It is possible that Yul Gok was originally performed this way, but the hooking block was changed to more closely resemble the actual hand position of grabbing an arm. The accompanying images for the hooking block in the 1965 book support this.
Regardless, the sequence in Yul Gok does not match the sequence in Wado's Yondan, only the block, but I felt that the presence of this block in Yul Gok was significant considering how much else is borrowed from Yondan. Choi's 1965 directions for "HEI-AN PATTERN IV" do not mention hooking blocks, but this is expected as they are not found in Shotokan's version of the pattern.
Yul Gok follows the hooking block sequence with a punch, then a side kick followed by an elbow. The kick-into-elbow sequence is very common in Karate kata, and it is performed on both sides in Yondan as it is in Yul Gok, (though at different angles).
The next movement is incidental. The twin knifehand block in Yul Gok is the opening movement of Yondan. However, the sequences are unrelated, and this is only mentioned due to, again, how many movements appear in both patterns.
After a few more blocks and punches, Yul Gok jumps forward into an X stance and backfist strike, shown below from the rear. This exact move appears earlier in Yondan, performed in the opposite direction with the other hand.
Yul Gok finishes with double forearm blocks to each side. While not in the same sequence, this same block appears in Yondan 4 times.
