I don't know where in the documentation the difference in behaviour between \skip1 and "" as opposed to _ is explained. But the opportunity is missed on these pages, the first of which actually conflates the "" and _ notation:
https://lilypond.org/doc/v2.25/Documentation/snippets/rhythms_003a-skips-in-lyric-mode-_00282_0029 https://lilypond.org/doc/v2.25/Documentation/snippets/rhythms_003a-skips-in-lyric-mode Paul
