“Those of the sword should possess an edge and rather break than bend. When the head is free of distracting thoughts, the heart of the sword is enlightened, and a single sword strike can destroy all techniques….” - Xiaoyao Zi
Like Sword Intent, the Enlightened Sword Heart was a state that Sword Cultivators dreamt of. Sword Intent was capable of boosting the strength of a Sword Cultivator by a great degree as well as restraining and suppressing the Sword Cultivator’s enemies. On the other hand, the Enlightened Sword Heart was capable of allowing a Sword Cultivator’s heart towards the Sword Dao to become purer, and it wouldn’t be deceived by anything while it could see through the essence of all things!
The saying destroying all techniques with a single strike of the sword referred to the Enlightened Sword Heart because those with an Enlightened Sword Heart were unafraid of the assault of all techniques!