diff --git a/Doc/library/email.message.rst b/Doc/library/email.message.rst
index 5ebc960..fa1df88 100644
--- a/Doc/library/email.message.rst
+++ b/Doc/library/email.message.rst
@@ -136,9 +136,10 @@
       :mailheader:`Content-Type` header. Anything else will generate a
       :exc:`TypeError`.
 
-      The message will be assumed to be of type :mimetype:`text/\*` encoded with
-      *charset.input_charset*.  It will be converted to *charset.output_charset*
-      and encoded properly, if needed, when generating the plain text
+      The message will be assumed to be of type :mimetype:`text/\*`, with the
+      payload either in unicode or encoded with *charset.input_charset*.
+      It will be encoded or converted to *charset.output_charset*
+      and transfer encoded properly, if needed, when generating the plain text
       representation of the message.  MIME headers (:mailheader:`MIME-Version`,
       :mailheader:`Content-Type`, :mailheader:`Content-Transfer-Encoding`) will
       be added as needed.
diff --git a/Doc/library/email.mime.rst b/Doc/library/email.mime.rst
index 10f3e37..a092feb 100644
--- a/Doc/library/email.mime.rst
+++ b/Doc/library/email.mime.rst
@@ -191,9 +191,11 @@
    minor type and defaults to :mimetype:`plain`.  *_charset* is the character
    set of the text and is passed as a parameter to the
    :class:`~email.mime.nonmultipart.MIMENonMultipart` constructor; it defaults
-   to ``us-ascii``.  No guessing or encoding is performed on the text data.
+   to ``us-ascii``.  If *_text* is unicode, it is encoded using the
+   *output_charset* of *_charset*, otherwise it is used as-is.
 
    .. versionchanged:: 2.4
-      The previously deprecated *_encoding* argument has been removed.  Encoding
-      happens implicitly based on the *_charset* argument.
+      The previously deprecated *_encoding* argument has been removed.  Content
+      Transfer Encoding now happens happens implicitly based on the *_charset*
+      argument.