I probably did not express myself very clearly. I did not intend to refute what you quoted from the handbook.
Since we were discussing if we should use the “to be best” or the “to limit” meaning for 限る, I wanted to point out that according to my searches, it seems that in the case of the “verb + 〜に限る” combination only the “to be best” meaning is applicable.
I think these two videos explain the different uses quite nicely:
The lack of clarity in expression was mine. I was just intending to add to the concept that the “is the best” is probably the most applicable one here (agreeing with you), with the additional comment that my understanding is that it can be used in a casual and not necessarily literal sense.
I think we are on the same page. 
D’oh. It took me a while to click in that the Handbook of Japanese Grammar Patterns for Teachers and Learners TobiasW referred to was the English version of 日本語文型辞典. I only have the Japanese version (I bought it close to 20 years ago) and was not aware there was an English version until I Googled it!
Sorry for the confusion by essentially double-posting.
Week 2 thread is up.
No, your post was on point. I was just surprised that the Handbook contains Nにかぎる, but didn’t mention that usage at all, so I was wondering if I’m misunderstanding you or if it’s missing from the handbook. Judging by the first video (thanks for sharing those!) it’s pretty clear that the latter is the case.
Yeah, this is no coincidence hahaha