The space is perhaps something a response to something that I've wondered about. The headings in the wiki don't get autonumbered, which combined with the quite subtle differences in type size from level to level can make it tricky to see the nesting structure. Obviously having actual autonumbered sections gives the temptation to hard-code section numbers in the text which don't change when stuff gets rearranged, but is there any other reason why there's not visible section numbering?

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