But, I'm wondering is there any major difference between just clicking the "..." next to the song in the default interface and selecting "Download->Audio"?
Q* or any X* for that matter is extremely common for referring to the optimal function under certain assumptions. (usually cost / reward structure).
Specifically, Pablo Román's effort to make this viable for Spanish [1]. I started before there was a website or anything, just watching free youtube videos. Now I'm definitely B2 or C1. I subscribe partially just to show my support even though I mostly consume native-level media now.
Similar and helpful along he lines of CI are [2] and [3].
[0] https://en.wikipedia.org/wiki/Input_hypothesis [1] https://dreamingspanish.com [2] https://refold.la/ [3] https://www.alljapaneseallthetime.com/
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