Inspired by Trader, I'm again looking into a frost-free sillcock.

The text and video pages seem to make a big deal out of tilting the pipe
down 5 degrees as opposed to up 5 degrees. Up is not the alternative in
my case, it is level. All the pipes are already there and the pipe
that goes outside is level.

If I do nothing, the new sillcock will be level too. It seems to me
that if the pipe I.D. is 1/2 inch, a level pipe will drain until the
water level is no more than 1/8", 1/4 of the total diameter, and that
even if it freezes then, it will expand UP into the air space. And
that 1/8" of water, or even 3/16" with all that empty space above can't
possibly freeze in a way that breaks the pipe. Won't it just lift
itself up? Clower to the center of the pipe.

(I reed that water expands a bit more than 9% when cooling between 4^C
and 0^C.)

Maybe at the end of the pipe, where the valve is, surface tension will
keep the water level higher, but that will be 6" into my basement, where
the temp is always about 68^. Can water freeze inside when it's 68F
outside.

I don't see how I can raise the other pipes to tip the sillcock down as
it goes out of the house. IIRC, a floor joist is in the way.