The book had only about thirty pages, which didn't take very long to read. A big part of the book was about rules regarding fighting, attending lessons, how to obtain Contribution Points, the functions of the room, and some general information.
From what Shang had read, fighting with one's weapon was forbidden, but fighting without a weapon was fine. The reason for such a choice was to preserve the killing intent in someone. If someone used their killing tool to spar with others a lot, they might lose their killing intent.
Because of that, the academy tried to preserve the killing intent of the weapon. One should only draw one's weapon when one intended to kill someone.
Of course, there were exceptions. For example, two students could schedule an official spar at any of the training areas. In that case, they could use their weapon.
But wait, how did that differ from just fighting normally? After all, it was also just a spar.