No: Tinderbox isn’t anything like this. That’s Heptabase: this is Tinderbox.
You can break a textual monolith into pieces in several ways. The easiest, probably, is to cut text here and paste it to make a new note there.
If you want to do that repeatedly in a really big note, you can place a delimiter where you want to slice the notes. That’s what Explode… does. There’s lots of ways to customize Explode, which makes it a interesting to talk about, but that’s all it is — a way to slice a text into a sequence of little texts.
What are these texts you want to reorganize? Are these the “notes files from 30+ years of personal journaling” you were asking about in December? Or something else?