The oplog option confusion clarification

source/reference/program/mongodump.txt

@@ -181,13 +181,14 @@ Options
 .. option:: --oplog
 
    Use this option to ensure that :program:`mongodump` creates a dump
-   of the database that includes an :term:`oplog`, to create a
+   of the database that includes a partial :term:`oplog` containing
+   duration of the mongodump command, which allows you to create a
    point-in-time snapshot of the state of a :program:`mongod` instance. To
    restore to a specific point-in-time backup, use the output created
    with this option in conjunction with :option:`mongorestore --oplogReplay`.
 
    Without :option:`--oplog`, if there are write operations during the
-   dump operation, the dump will not reflect a single moment in
+   dump operation, the dump will not reflect a consistent point in
    time. Changes made to the database during the update process can
    affect the output of the backup.
 
@@ -201,7 +202,9 @@ Options
       :option:`--oplog` only works against nodes that maintain an
       :term:`oplog`. This includes all members of a replica set, as
       well as :term:`master` nodes in master/slave replication
-      deployments.
+      deployments.  
+
+      :option:`--oplog` does not dump the oplog collection.
 
 .. option:: --repair