Writing this kind of explanatory prose text also raises needs for tools that we don't quite have on
tiddlywiki.com.
Compound tiddler: I imply the most obvious problem in the OP; How do we create a linear document from tiddlers. Currently, on Jeremys recommendation, I'm using one encompassing tiddler (the main Big Pic tiddler) with hard coded transclusions inside.
Doc-ToC: As discussed many times, some kind of ToC for a compound tiddler is of course also needed.
Inline asides: In abandoning "paper" we should obviously take advantage of the TW features. As seen in the tiddler "Custom Fields", I've included two "popup pills" to show some lists. Accessing them helps understanding but they can't reasonably be shown mid-text. In the original text I settled for showing the code how to generate them ("If you type `{{{ [...] }}}` ") but this is also a cop-out. The current "tag pill" method is an OK solution but the styling is probably not suitable. I'd prefer it to not visually break the text, perhaps more looking like a link but it should be clear that clicking it would show a popup so one doesn't leave the current tiddler.
Apropos: Somewhat related to the previous, but in these types of texts there are sometimes "by the way" bits that are not part of the text at all but still relvant to what is discussed and of value for the reader. For example, in the section on Templates and how a tiddler lists these, I wanted to do a side note that "You can easily create your own templates by by tagging a tiddler ... and it will be listed along with the other templates in all the tiddlers" but this is a side step and would be better as a little floating "information frame" styled with a border and different background.
So, my point is that when authoring
documents, there's a need for these kinds of tools but they don't exist on
tiddlywiki.com nor in TiddlyWiki.
<:-)