At 1900 -0600 12/18/02, Billy Bob wrote:
> At 1855 -0600 12/18/02, John Doe wrote:
> > This is a test.
>
> This is also a test.
Your test worked.
Note that quoted text goes above a reply, not below it. Note that there's a line saying who wrote the original post. Note that every quoted line is preceded by both an angle bracket and a space. Note the blank line after the quoted text. Note the complete lack of either Billy Bob's or John Doe's initials before their respective quoted sections. Note that this format is very easy for a mail client to manipulate in order to make it easier to read.
Why don't more mail clients use the One True Quoting Style, or something even remotely approximating it?
(My guess is that it came from something like PROFS and has since become institutionalized. Whether it's just an IBM-ism that became "the way it's done" or it was made that way in response to corporate requests, I don't know.)