🚀 go-pugleaf

It's true that if a large source posting appears in newsgroup X which
isn't fed to your site, then merely *pointing* to it in alt.sources
doesn't help a great deal if you decide you actually want that source.

But that's an acceptable risk.  If you don't get a feed for newsgroup X 
in the first place, it's reasonable to suppose you're not interested in
its contents -- including large source postings that might appear
there.  So forcibly reproducing them en masse in alt.sources is more
likely to be an annoyance than a help.  In short, if you can't follow
a pointer, you probably don't want to.

In principle you are as likely to be uninterested in short sources 
from unwanted newsgroups as you are long sources; but because the net
expense and annoyance from gratuitous short source postings is smaller,
this too is an acceptable risk.

The problem with all those headers is they (plus the existing required
headers) frequently rival the actual source code in size!  Too much
overhead.  Alt.sources should be informal.
-- 
"Nature loves a vacuum.  Digital    \O@/    Tom Neff
  doesn't." -- DEC sales letter     /@O\    tneff@bfmny0.UU.NET