Question: ZMAIL mailing vs ZWEI mailing.

[Richard M. Stallman <RMS at MIT-OZ>]

In ZWEI, mailing with the C-X M command separates the headers and text
with a line --Text Follows This Line--.  In ZMAIL, when the headers and
text are in the same window, they are separated by a blank line.

Many people have complained about the difference between ZWEI and
ZMAIL in this regard, so I would like to make them the same.
My question is, which of the two ways do people prefer?
Should a blank line separate them, or should a line that says
what it does separate them?