In article , shannie
writes

That being said, the abc actually doesn't refer to top or bottom posting as
far as I can see, just to the nonposting of binaries and editing down
messages to keep them concise.

It says this:

(2) When you are replying to a message, it's a good idea to edit down
your quotes (snipping) to the point(s) that you are actually addressing,
but be sure that you have kept enough in to make it intelligible!

Ok, maybe it is not entirely clear so perhaps we should make it a little
more explicit.
Incidentally, we named it abc because some news readers organise posts
in alphabetical sequence. On those readers it would appear at the top.
--
Jane Ransom in Lancaster.
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