In Gu Long's LUK SIU FUNG novel series, the Ngor Mei Sect Leader Dook Goo 1 Hok had the extraordinary skill of being able to instantly locate and seal the weaknesses in his own sword technique, making it effectively impossible for foes to exploit whatever weaknesses they might find in his technique. Even Sai Mun Chui Sheut, who is known for a killer sword style that specializes in attacking weaknesses in the enemy's technique, was unable to penetrate Dook Goo 1 Hok's defenses until Dook Goo 1 Hok ran out of inner power (which only happened because Fok Teen Ching had drained Dook Goo 1 Hok's inner power just minutes before Dook Goo's duel with Sai Mun). Had Dook Goo 1 Hok not been drained of inner power before dueling Sai Mun Chui Sheut, Dook Goo 1 Hok would likely have defeated Sai Mun Chui Sheut.
Dook Goo Kau Bai's Dook Goo 9 Swords followed a principle similar to Sai Mun Chui Sheut's sword technique: it was purely offensive, exploiting the vulnerabilities in the enemy's technique. While Dook Goo 1 Hok might not have been good enough to defeat Dook Goo Kau Bai himself (Dook Goo Kau Bai had more than Dook Goo 9 Swords going for him, after all; he could switch to Heavy Iron Sword mode or No Sword mode), perhaps Dook Goo 1 Hok could have beaten such latter day Dook Goo 9 Swords practitioners such as Fung Ching Yeung or Ling Wu Chung...neither of whom was known for impressive inner power and whose inner power was likely inferior to Dook Goo 1 Hok's (like Sai Mun Chui Sheut's was)?