> I encourage you to submit the name of an OS in which non-trivial OS
> upgrades are this automated.  I've not met one in the last 10 years,
> but maybe you have.  If so we'll look it over for ideas. :-)

Linux.   More/BSD.   Supposedly More/BSD's upgrade path was very good
about not trashing system files.   I don't know how well Linux's
automatic upgrade really works, because I've only tried it once, but
they do make the claim of a truly hands-off upgrade.   It probably
helps that they have a SysV-ish rc.

			       _MelloN_