[Previous text and attributions tidied somewhat, but sequence
deliberately retained]

PJ Hunt wrote:

Thank you for that well thought out informative response to my post.

Bob Ward wrote:
PJ Hunt wrote:

I'll stick to this type of posting unless someone can explain why
it's better to repost the entire message at the top of my reply.

That's fine - a lot of us won't see it anyway.

Do you see what has happened here?

Simplifying somewhat, the structure is something like:

Comment 2

Original text

Comment 1

Yuck!

It is clearly preferable to maintain a *consistent* pattern, either
*always* placing new text before old ("top-posting"), or *always*
placing new text after old ("bottom-posting").

For *very good* historical reasons, the convention on Usenet is to
place new text *after* the old text on which you are commenting,
snipping out *surplus* old text and, when commenting on a number of
fragments, placing each comment immediately after the relevant bit
of the old text.

This way, reading an article from top to bottom should make sense
in a question-and-answer kind of way. Readers who are sufficiently
familiar with the thread can skip over the quoted text, but it will
generally be available for reference simply by looking a little way
up the screen, rather as one sometimes looks back at the previous
paragraph in a book.

*One* of the reasons for quoting and commenting in this way is that
Usenet articles are *not* guaranteed to arrive at a newsserver in
the "correct" order - heck, they are not *guaranteed* to arrive at
all - and propagation delays can be quite substantial: Google take
their time even now, and once upon a time delays measured in *days*
were common.

In the early days of Usenet, *slow* and *expensive* net connections
were very common, which made snipping out excess quoted material a
Very Good Thing. Things aren't *as bad* these days, but some users
are still on slowish connections where extra bytes cost extra bucks,
so good snippage is still very good practice.

Usenet and email are two *very* different media: Usenet is a form of
*broadcast* medium where readers often find themselves dealing with
fragments of *many* threads at once; email is basically a one-to-one
medium (yes, spammers abuse it as a broadcast medium) in which you
can be far more certain that your correspondent is already familiar
with the topic of your reply, so that *appending* the previous text
for reference makes more sense. That said, interleaving old and new
text in email responses can be very useful - particularly where the
discussion *is* a series of questions and answers.

This is a bit longer than I had anticipated, but I hope you can now
see why "bottom-posting" is conventional on Usenet.