Well, the long and short of it is that the stick-fix worked.

When I pulled to a stop after the heater erupted, I was parked next to a
Chrysolepis chrysophylla (Golden Chinquapin) which is a smooth-skinned oak
with elliptical evergreen leaves.  I stuck my fingers into the hose until I
found which one fit the best, then used that to size an appropriate branch,
cut a couple of staubs, and clamped them in place.  The engine still
overheated and blew steam through one stick, so I had to drive down to the
creek to get more water since the expansion tank was empty.  

After filling with water and purging the system of air, I started the engine
and ran it until the temperature increase finally tripped the radiator fan.
This took quite a while, so I took pictures while waiting.  This is the
creek where I was stranded: http://tinyurl.com/m2alg4.  After I had
determined that all was well, I had lunch and played banjo at the falls for
a while.  

The climb from 3,500 up to the 5,000 ft elevation didn't even get the
temperature up to the mid-way mark, so I was feeling confident that I didn't
need to take the long route home out to Highway 97 and around through
Chiloquin, and instead I took the shortcut (which was my original intent)
through Crater Lake.  (Crater Lake as in
http://en.wikipedia.org/wiki/Crater_Lake.) That may have been pushing it,
but all was well.  That is a long hard climb for a Westy, and by the time we
reached the rim the temp had maxed out.  But this time it was acting
normally: it would reach a peak, the fan came on, and it would recede a
little.  At the top I checked my sticks.  They were still dripping a little,
but not enough to worry about - and the climb to 7,000 was over!  

So, contra park rules, I gave the scraps of my lunch to a friendly golden
mantled ground squirrel (they apparently like pickled olives & garlic and
pepperjack cheese...) and then drove another 41.1 miles to the folks place.

I suppose it ain't over 'til it's over, and I'm now looking for a heater
core...

I'll be back from a 'Vegas business trip next week, back in the Westy and
looking for more adventures.

Matt
________________________________________
From: Matthew Snook
Subject: [VWVANFULLTIMERS] rear heater blowout - stranded: Chapter Two
� 
OK, the sticks are in place. I used some golden chinquapin big enough to
fit in the hose end, put the clamps back on and...