The experiences of another major mail system (AT&T Mail) which provides for
attachments of this nature indicate that the proper place for the main
message is at the beginning of the message and not at the end. You normally
attach an item to something. In order to do that attaching, you first have
to have that something. So you provide the something first so you can do the
attaching.
Tony is absolutely right on this one -- practically everyone else has the main
message first and the attachments second. It just works better this way; not
only is it critical to the information flow for the sender, it is also the
natural ordering and thus it is critical to the receiver as well.
Ned