Following on from the last post about WordProcessingML list gotchas, another piece of obscure information about lists, is that you can’t technically restart them. Restarted lists are actually new w:list definitions, which may or may not point to an older w:listDef.
The problem here is that if you’re constructing a Word document from multiple parts or documents, then you need to keep track of how many lists there are in a document, and what their IDs are, because you’ll need them all at the end when you create the various w:list structures you’ll need to point to them all.
In Word every list is unique. If you restart a list with the UI, under the covers it actually creates another list which just points to the same w:listDef, so you can change the style of all the restarted lists in one place, but it causes havoc when you want to convert multiple HTML <ol>s to Word lists.