Well to my knowledge, the blade itself (lol) was never actually described, only the pommel as being oddly curved (and, correct me if I'm wrong, but the pommel refers to the base of the hilt and is meant to avoid slippage as well as acting as a counter-balance, which in-and-of-itself is not particularly descriptive of a katana). I actually originally envisioned it as something like the Chinese jian, but with a long, curved pommel. Then, at some point, my mental image morphed into a katana. Truth be told I don't really know what exactly Bakker's going for with the descriptions of Certainty.