SR

FYI, the text of the clue for 62A has the correct cross-references, but for me it highlights 49D instead of 49A.

On 33D, Ismo explains it all: <a href="https://www.youtube.com/watch?v=RAGcDi0DRtU" target="_blank">https://www.youtube.com/watch?v=RAGcDi0DRtU</a>

Congratulations! (So we know your kids are also talented constructors; have they ended up on the sweet side, the competitive side, or both?)

As XWordInfo notes, "The app at the Times takes PHI or IO or OI or O or I or various other combinations as correct." But why doesn't it accept the ɸ character? (I had to go through the whole puzzle changing those squares, but I'm not even annoyed because the theme and mechanism were so brilliant and the whole puzzle was so high-quality.) Kudos to Dylan!!!