+** Redesign to use two buffers for one message
+
+ MIME-View is based on "Multiple Representation Space (layer) Model".
+In this model, network representation and its presentation are
+distinguished. Thus MIME-View uses two buffers for one message,
+'mime-raw-buffer (for network representation) and
+'mime-preview-buffer. MIME-View manages them based on information of
+entities. According to experience of MIME-View, this model is good to
+treat complex structured data, such as MIME.
+
+ MIME-Edit was designed to use one buffer for one message. So it is
+hard to edit like WYSIWYG style. Format of tag is limited by
+translation. Content of forwarded message is unreadable. It is
+better to introduce "Multiple Representation Space Model" to resolve
+these problems.
+