Make Co-Citations take outliner structure into account

[HEmile]

Similar to how we deal with headings, we can also take the structure of outlines into account. However, this conflicts with the weights given for sub-headings! How do we properly choose those weights?

Problem example:

# H11
[[A]]
## H12
[[B]]
# H12
- [[C]]
    - [[D]]
# H13
[[E]]

[[F]]

What should the weights of the co-citations (A, B), (C, D) and (E, F) be?