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Nalizar is teaching his students to focus on an offensive style while neglecting defense. With the context that this is useless against wild chalkings, the thing they are actually meant to be fighting, and that he's trying to sabotage humans then his fighting style takes on a new light.
His behavior also makes sense as most of the stuff he learned about humans comes from books. From the descriptions we get it seems accounts focus only on the actual battles, so it makes sense that when he challenges Fitch he doesn't even bother to mention his intent. None of the books probably mentioned that bit.
Both Harding and Nalizar are mentioned to use unconventional methods for drawing chalk, one with the chalk attached to a rifle and another a shoe. Both also aren't fully human.
