random questions mostly about Gnus configuration variables

[Joe Wells <jbw@cs.bu.edu>]

Hi, Gnusians,

Here are some random questions mostly about Gnus configuration variables:

1.  The doc string ("C-h v") of gnus-fetch-old-headers is unclear.  The
    doc string seems to imply that Gnus will scan the "references" headers
    of the articles and then request the headers of the referred articles.
    But in fact, setting this variable non-nil seems to make Gnus blindly
    fetch all of the headers in the newsgroup.  What really happens?

2.  What is gnus-simplify-ignored-prefixes used by?  The doc string is
    unclear.

3.  The doc string of gnus-build-sparse-threads is unclear.  What does
    this really do?  What are the "gaps" to which the doc string refers?

4.  What in the world does gnus-group-use-permanent-levels do?  The doc
    string is utterly baffling.  What does it mean by "once you set a
    level"?

5.  How do gnus-auto-subscribed-groups, gnus-options-subscribe, and
    gnus-options-not-subscribe interact?

6.  What is the difference between nil and 'some for
    gnus-read-active-file?

7.  Why did I see the message "Loading hexl" while Gnus was fetching
    headers for a group?  What does Gnus use "hexl" for?

8.  What is "~/Mail/drafts" for?

9.  What are the interactions between the to-address, to-group, and
    to-list parameters of a group?  What happens if you set more than one
    of them?  What is the difference between to-address and to-list?

-- 
Joe Wells <jbw@cs.bu.edu>