XLN as fast with the sword, but against regular QZ daoists. So this is not a good measure of her speed relativeto mongol mercs. And it seems shedrew two swords i/o one.
Third paragraph of chapter 26
Paragraph 4+5"Before their hands reached her sleeve, the fight, from their perspective, was moving as fast as lightning, and then their wrists felt a burst of severe pain. In haste they leapt back. What had happened was that from her waist Xiao Longnu pulled out two swords. In the blink of an eye, their wrists were struck by the swords; the carpal bones were almost broken and the wrists were drenched with blood."
It specifically states that L/R is what sped her up many times."The thrust of the two swords was even quicker than before; even experts such as Xiaoxiang Zi and Yin Kexi gazed at each other with pale faces. They’d previously seen her fight Gongsun Zhi at Passionless Valley. At that time her sword stances were fine and ingenious, but they were definitely not as unbelievable as they were now.
Xiao Longnu was taught how to separate her mind for two uses by Zhou Botong, the Left/Right Mutual Combat Technique; between her innate abilities and his teaching, her martial arts had multiplied. With Yang Guo forming the Dueling Sword Combination and using the ‘Pure Heart of the Jade Maiden Sword Technique’, few have matched it under the heavens. Now, as one person, she can use two swords simultaneously, with outstanding power. Regardless of how two people’s intentions are interlinked with each other, it’s still inferior to one person’s lightning-like alertness during battle. At this moment, although her sword method’s energy and strength weren’t as good as two people teaming up, her moves are faster in comparison by many times. "
XLN was unaware of her own abilities. Much like GJ in LOCH when he used L/R the first time against OYK. Hence, this is why I tend to believe that GJ still has room to maximize on L/R just like XLN if he were somehow to figure out he can just shoot mini blasts of finger snaps.Xiao Longnu studied her Left/Right Mutual Combat Technique alone and practiced it a couple of times in the wilderness, but she’d never exchanged blows with anyone. Today she had the opportunity to try out these new techniques, and even she could not have dreamed of possessing such might; she was unexpectedly startled.
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And upon further reading myself. I realize that the fight between her and the mongol mercs was quite a convenient fluke for XLN. It just so happens she has lots of swords to fling in the air, w/o multiple swords, she wouldn't be "unblockable fast" to the mongol mercs. XLN using 2 swords was still at a slight disadvantage to the 3 mercs (although it would require all 3 to beat her).
I also still can't understand why XLN seems so fast GWM when GSZ obviously can keep up. So either GWM brainfart was truly bad (since JY mentioned many times he was loosing more psychologically against XLN than by pure combat prowess), or XLN got a good ol' fashion JY protagonist plot device boost.