Nice appeal to (non-existent) authority. Every functional Usenet
group I've ever taken part in (since about 1991) has insisted on far
less rigidity than you're attempting to impose here.
The amount of rigidity expected of groups tends to vary widely with both
topic and scope. In this case, experiments were tried in the distant past
with not pushing the issue much, and the net result was that the group
got swamped by posts which were of even potential interest to only a minority
of participants.
And you'd never be caught doing that, would you. If you wish to impose
standards on others, you'll find you'll get more traction if you make
a token effort to stick to them yourself.
A token effort, but...
For example:
i) don't get involved in a long discussion about the naming of a UNIX
daemon (take it comp.unix!)
I did, in fact, frequently set followups, and I studiously avoided the
substantial Unix content that would have occurred if I'd been writing in
a Unix group.
ii) don't continually respond to the off-topic ramblings of spinoza111
with the sole defence that "It's funny"
I would argue that the underlying substance of those discussions was
topical -- comments on the quality of C books and of reviews of them is
topical. However, you'll note that about the second or third time that
someone asked me to stop, I plonked him and stopped. (Second or third
time, because I wanted to think about it a bit. I did eventually conclude
that there was no risk at all of him convincing anyone sane.)
Otherwise, you'll just look like a complete hypocrite.
I could hardly hope. I think, like every other living human, I'll have to
settle for a partial hypocrite.
-s