Porridge (without mystics) is a gelatinized starch. Your remarks about
wheat porridge bread were just in time: reading Auerman's book posted
by Ronald Fieldstein in the past the following was found about porridge
bread (these are only extracts and conclusions):
Wheat bread:
- to make the porridge 5-10% of the whole amount of flour mixed with
triple amount of water to gain about 70C temperature (not 62-65C!). The
result: starch is gelatinized.
Afterwards the porridge could be:
- saccarified (by autosaccarification with amylases of the flour or
adding malt) at 62-65C
- left "as is"
- salted (to make "salt porridge")
- fermented with SD or yeasts
Experiments have shown that the best thing for wheat bread is to leave
porridge as is w/o saccarification. It is absolutely necessary to make
porridge when adding "adjuncts" like oat or maize (corn). General
conclusion: porridge improves the wheat bread when the flour is weak to
produce enough CO2 and/or sugar.
Rye bread:
Jumping directly to conclusions: only saccarification (preferably with
rye or barley malt) of the porridge does make good to rye bread and
substantially improves it.
That means that you (and Ortiz) are right: the porridge w/o
saccarification (mashing) does exist. Actually, temperatures of mashing
(62-65C) are lower than that of "simple" porridge (70C) because this
70C temperatures aims to kill (denaturize) amylase ferments.
Exciting.

Leonid