In lieu of my "bring to boil and remove from and let sit in the water 15
minutes method", which cooks perfectly but has occasional peeling problems,
I tried the following and just finished the test:

8 fresh extra-large eggs (these hens were apparently fed only grain,
according to the carton)
4 quite old extra-large eggs (expiration date from last week -Mar 23)

self-defrost refrigerator is about 38 degrees, eggs in carton are stored on
top shelf near the fan

850 feet above sea level

cold tap water

pasta cooker (enamel, deep, fits the large burner completely - has an insert
that sits above the water for lifting pasta, an insert colander, and an
insert colander strainer-cover. I removed the colander equipment, using only
the insert.)

about 2-3" water, to just below and not touching the insert where the eggs
rest.

the eggs went into the insert and into the pot, then I put the water in the
pot and placed the covered pot on the stove, on high.

Just before water boiled, I turned the burner down to low (it kept the water
at a low boil and the pot was full of water vapor).

I timed from when the water boiled (from visual check and by sound)

12 minutes steamed (the eggs were extra large, and I plan to devil them if
they cook fully, so I guessed an extra two minutes more than large eggs)

12 minutes resting

I put an equal amount of cold water in the pot, then dumped it all out and
put enough cold water in the pot and insert to cover the eggs with two
inches cold water.

I pulled two eggs in 6 minutes and let them drain.

I drained the others in 12 minutes.

Results:
One of the new eggs cracked longitudinally, but the egg did not part and no
white came out of the shell.

I cracked a new egg - the white was not firm, but not runny - it was
partially cooked.

The old egg had the same result -not fully cooked.

I am now returning the remaining eggs to the steamer for an additional ten
minutes in steam and retesting.

Based on these results, I would guess that it will take about 18-20 minutes
steaming rather than 12 minutes for an extra large egg, when doing a dozen
eggs at once.

More at next test.