SCN does sort of have some "sticky functions".
Within the communication stream and announcement can be set for users who follow the space. However, Moderators do not have that access. This might also appear at the top of the space page.
Another option is that Featured Content on the space page. This is managed by the Spaced Editors. Looking at the ABAP space there is quite a lot of Featured Content which looks a bit messy (most spaces pick 3 or 4 items at a time).
The Space Editor could also add the document to the Key Topics link on left side but it might not be noticed.
However, neither of this will show in the Activity Stream which is where some users may find the information.
Biggest challenge - those who need to read such a document probably won't see it until after their content is rejected.
Though, 1DX changes this