I agree it's terribly named, however discussing the behavior of strncpy is important because the casual reader or new C programmer will see "don't use strncpy,

I agree it's terribly named, however discussing the behavior of strncpy is important because the casual reader or new C programmer will see "don't use strncpy, it's broken" and then come away with the wrong idea. strncpy is not inherently broken but it's most likely not the correct function to use. As a C programmer it's important to understand why and what the alternatives are (and there are several).