DOCS-877 cleanup of faq snapshot and tutorial cursor info

source/faq/developers.txt

@@ -549,12 +549,12 @@ the data returned by the query will reflect a single moment in time
 
 .. warning::
 
-   You **cannot** use :method:`snapshot() <cursor.snapshot()>` with
-   :term:`sharded collections <sharding>`.
+   - You **cannot** use :method:`snapshot() <cursor.snapshot()>` with
+     :term:`sharded collections <sharding>`.
 
-   You **cannot** use :method:`snapshot() <cursor.snapshot()>` with
-   :method:`sort() <cursor.sort()>` or :method:`hint()
-   <cursor.hint()>` cursor methods.
+   - You **cannot** use :method:`snapshot() <cursor.snapshot()>` with
+     :method:`sort() <cursor.sort()>` or :method:`hint()
+     <cursor.hint()>` cursor methods.
 
 
 As an alternative, if your collection has a field or fields that are
@@ -571,6 +571,6 @@ explicitly force the query to use that index.
    query; then the cursor will return the same document more than
    once.
 
-.. [#id-is-immutable] MongoDB does permit changes to the value of the
-   ``_id`` field, it is not possible for a cursor that transverses
+.. [#id-is-immutable] MongoDB does not permit changes to the value of the
+   ``_id`` field; it is not possible for a cursor that transverses
    this index to pass the same document more than once.

source/tutorial/getting-started.txt

@@ -344,14 +344,14 @@ the following procedure:
 
       { "_id" : ObjectId("4c220a42f3924d31102bd858"), "x" : 4, "j" : 3 }
 
-   When you access documents in a cursor using on its indexed position
-   in an array, :program:`mongo` must iterate all documents with lower
-   index values.
-
-   For example, if you access the document at ``c[4]``,
-   :program:`mongo` must load and iterate through the documents at
-   ``c[0]`` through ``c[3]`` in addition to ``c[4]``.  For very large
-   result sets, :program:`mongo` may run out of available memory.
+   When you access documents in a cursor using the array index
+   notation, :program:`mongo` first calls the ``cursor.toArray()``
+   method and loads into RAM all documents returned by the cursor. The
+   index is then applied to the resulting array. This operation
+   iterates the cursor completely and exhausts the cursor.
+
+   For very large result sets, :program:`mongo` may run out of
+   available memory.
 
 For more information on the cursor, see :ref:`crud-read-cursor`.