This is Revision c) of the document. I somehow forgot to mention the FreeNAS User Guide in the Further Reading section - that has been fixed. I also added a section on the recordsize property.
Besides that, a footnote was added to the dedup subsection guiding people towards FMAZ if they really want to know more about dedup. I also added the links to the Resources section and to the Resource page to the first page of the document.