> 2) "session-keyfile" is documented as taking a path, not a keyword.  So
> how does one
> know to specify "none" to disable the feature... I just rechecked the
> 9.10 ARM and
> don't see any hint of this. 

Yes, this definitely needs fixing.

> And I don't think a reserved filename is a good idea.  "none" should
> create a file
> called "none", just as
>    zone example.net { type slave;  file "none" };
> would :-)

You get a file called "none" if you put it in quotation marks, which are
required for filenames anyway.  "session-keyfile none;" means no keyfile
(or key).

I will consider the other suggestions.