My car has turned into some kind of monster.  Check out this MFD:

This was the tank prior to my fillup somewhere in mid Pennsylvania,
shortly before diving onto the local roads toward Lancaster.  The tank
had been all interstate, including a stop for the night.

This was just after entering the Delaware Water Gap area, after
a mix of major and secondary highways.  Over 200 miles, down one
pip on the gas gauge.

On the way home I decided on a whim to divert off I-84 and tool
up the hill to High Point in NJ, which I don't think I'd ever
actually been to despite having grown up in the Landfill State.
It's a respectable bump in the landscape, so despite trying to
empty the battery with EVing before descending there was a bit
of engine-pumping and brake-heating on the way back down.  Small
loss, evidently; it didn't seem to affect the average much.

The rest of the trip home was *all* interstate, and I finally
arrived home near Boston with about a third of a tank left and
68.9 showing on the MFD.  This is pretty much *unheard of* MPG
average for highway travel in a Prius II, especially when I was
probably averaging about 62 mph and maybe a bit more than that
as I neared home.

What happened?  Did someone put "Bubba's gas enhancer pills" into
my tank at Hybridfest, or clip cow magnets around my fuel line
when I wasn't looking?  Did I pump a particularly spunky load
of summer-blend gas?  Did I pump diesel in by mistake and thus
gain more energy content?  Did I have one of Wayne's sweaty
shirts somewhere in the car?

No.  This is all happening because of controlled conditions.

   Highway travel MPG that makes Insight drivers take notice?  Doable.

   The mid-speed problem?  Solved, at long last.

   Best pulse technique?  Not only easy, but now fully explainable.

It's not about babying the accelerator.
It's not about how long to pulse or glide.
It's not about battery current or SOC.
It's not about cruise control.

What the hell is it, then?

It's all about shaft load, warp stealth, and patience.

After a year and a half, I have finally discovered the awesome
power of the HSD and heretical mode.  Part of the answer was always
right there in front of me on the first instrument I fooled around
with installing in the car, the vacuum gauge.  What's missing is
a display to show when you're really in the engine's efficiency
peak.  By a certain amount of dumb luck, I now have a simple "sweet
spot meter", and it has been making *all* the difference.  It's a
somewhat arbitrary representation of injector duty cycle, but the
range it happens to be displaying now is the right one to watch.

A full writeup on this will be out as soon as I collect some hard
numbers and pull all the facts and reasoning together.

_H*  060725