All of Tang Ling's battles had been secretive except for the first exam in which he purposely exposed his abilities under the public eye.
That particular battle with the Leceister silverback bear was considered astonishing and surely left a deep impression on everyone.
In fact, with the support of his Precise Instinct, every battle that he had been through was near perfect, including that very first virgin battle against a mutated beast, the black horn purple-striped snake, that Quark witnessed.
As for the battle with the chameleon black-winged mantis, had there been viewers around, they would have surely been amazed by the dance on the blade tips. What else could be a better sight than that?
Actually, it could be better like the acknowledgment of the Level 3 mutated insect's self-consciousness that could have been added into his Precise Instinct calculations.