Great question. The sol documents you refer to are the Mission Manager and Documentarian reports that provide a view into science operations—insight into why and how particular observations were made. The reports have not been edited except for grammar and spelling, and to remove spacecraft and instrument sensitive materials.
As you note, the sol documents are not part of the formal science archive. They are provided courtesy of the respective mission science teams who approve the content. Separate from the sol documents are mission and data set documents that are collected from archive bundles and volumes and are designed to promote understanding off the mission, spacecraft, instruments, and data formats.
I have updated the online help to include a more detailed description of sol documents, highlighting the fact that they are not part of the formal archive.