But teaching the Kun’yomi for 明. A full two-thirds of the vocab uses the on’yomi, in all the standard cases where you would expect onyomi instead of kun’yomi. This makes it confusing to learn kango words.
Same for 太, almost 2/3rds of the readings use the on’yomi, in all the cases you expect on’yomi to be used, but the kanji teaches the kun’yomi. What happened?
I don’t think this makes any sense. If the on’yumi reading is legitimately unused, then just omit the reading, or teach the kanji as a radical and skip directly to teaching the kun’yomi in a vocab.
Like 矢, since no vocab uses the on’yomi reading, why not skip the kanji lesson and go directly to the vocab lesson?
Decision-making process aside, you can’t necessarily use the number of examples to judge the relative frequency of the reading usages in the real world. (Also, some of those on’yomi examples are definitely there in order for you to use a reading you already know to help reinforce something new that you’re learning, for example when 太陽 in level 15 is brought back in level 25 as 太陽系 - this isn’t meant to be yet another example of 太 in action, but rather a new example of 系 in action.)
Because the steps are building blocks. Sometimes the building block feels superfluous, but if you’re building a house and you try to skip from the foundation to the roof because building walls is repetitive, the house ain’t gonna stay up.
(But yeah, Jisho’s only got five words that use the on’yomi of 矢; three of them are anatomical/medical terms and the other two are compound words. You’re probably not gonna encounter that one in the wild. )
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