In article Z9s%b.129328$uV3.645040@attbi_s51,
net says...
As a follow on to this, I'm wondering if my practice of cutting out
most of the prior discussion and just leaving the parts I'm replying to
is considered a good practice or not. My presumption is that people
have a newsreadeer that shows then the messages arranges as threads so
they can look above to prior postings for the rest of the info. Is
that right, or am I expecting too much?

You should trim your followup so that just enough information is left
for the reader to understand what you are replying about.

Every newsreader I've ever used, deletes (or at least hides) articles
after I read them. If I read a post today, and someone responds
tomorrow I'll have no idea what exactly the second person is replying to
if they remove all the text.

Looks like you are doing fine.
- Ken