Ping Xananews non-techies

Non-tech in my Xananews messagebase recently reached 130,000
messages... Well, it's time to cut out this thing.

How do you maintain heavy-traffic groups like b.p.d.non-technical in
Xananews?
When you reach a certain number of messages, do you archive them? Or
just delete them?

PS: I don't like XN archiving, I like to have all my messages in a
threaded view and archived messages in XN doesn't have this feature.

PS 2: If I delete messages I know I can find them in Google Groups, but
sometimes I need the NGs messages offline, also I prefer a "real"
threaded view when reading messages, not the way Google present threads
in a web page.

--
José
.