I was getting tired of seeing piles of series of partial content 206 requests in my logs, most likely from pdf read-while-loading browsers. So I set "accept-ranges none". The number of 206's went WAY down after that. But there still are a few, occasionally. Why? Maybe I misunderstood, but I thought that setting told the client that it had to grab the whole resource at one time.
I guess I'm wondering why, if partial content requests are supposed to be rejected, how is it that some such requests manage to get through?