Had a quick chat with Tony Hillman and wanted to clarify for all those on the ticket.
"Couchbase Server supports durability for single-document writes only. "
is a correct statement (assuming durability is the synonymous for synchronous write)
And in fact it would be incorrect to state
"Couchbase Server supports durability for multi-document writes. "
However from a development perspective we understand that including the statement "Couchbase Server supports durability for single-document writes only. " can be confusing to the developer. As from this the developer might assume we do not support transactions, when in fact we do as described https://docs.couchbase.com/server/current/learn/data/transactions.html