Notes: Formal. No kiwami and no itari mean exactly the same thing and are also exactly the same grammatically. The only difference is that no itari sounds more humble.
khongbietboi, according to my JLPT1 grammar book what you are saying isn't entirely correct. no itari can only be used for the speaker, whereas no kiwami can be used for others as well. so they are NOT exactly the same.
Everyone, according to my JLPT1 grammar book, an important difference between の至り and の極み is that the first can only be used for yourself (the speaker), whereas the latter can be used for others as well. Hope that helps
I am not sure if you can categorize 至り as relating to emotions and 極み as not. 光栄の至り、汗顔の至り and 慶賀の至り, etc., may not just relate to emotions. It is hard to set up any rule to differentiate.
Can somebody confirm if 〜の至り is used only for emotions. 贅沢(ぜいたく)の至り and 低俗の至り are wrong because they are not emotions. Right? They should be 贅沢の極み and 低俗の極み right?? Is ther an easier way to tell the difference between 〜の極みand 〜の至り?
I read that this is mainly used with experssions of emotion. 光栄, 感激, 若気,感心, etc are commonly used. It is ofen inerchangable with 〜の極み but 〜の極み is also used for words of non-emotion such as 疲労の極み.
maybe [noitari] has more of an implication of something that lead up to this situation? like [niitaru] - same kanji 至る