Privacy Issues re JA's Letters

It is a (claimed) truth (nearly) universally acknowledged that CEA,
before she died, destroyed a number of JA's letters out of concern for
the privacy of the deceased JA and/or of CEA or other members of the
Austen family.

There is a certain irony in regard to the above, in that it is another
(claimed) truth (nearly) universally acknowledged, that the letters JA
wrote to CEA were typically not read by CEA alone, but were passed
around to other family members who were with CEA at the time of her
receipt of a given letter from JA. I.e., there was not a whole lot of
privacy between JA and CEA with regard to those of the letters which
were actually passed around, at least within the family circle.

There seems something a bit perverse in the notion of preserving privacy
for a dead person, when that same person (JA), when alive, had to take
into account a rather serious lack of privacy in the reading of her
letters by family members other than CEA, when JA was composing those
letters!

The first claimed truth has, I think, been discussed often over the
years, and does not warrant fresh consideration, but I think the second
one has not received the critical attention it deserves.

One example of a critical comment I found, which I believe is typical,
is Chapman's, in his 1932 Second Edition of the Letters, when he
blithely opines:

“….They were from time to time separated by long visits, and then
corresponded regularly. But the purpose of their letters was to exchange
information not only between themselves, but between two branches of a
large family. There are indications that these letters and others like
them were ready by, and to, a number of people. …“

I say "blithely" because he fails even to consider the possibility that
JA might, during at least some of these long separations, have wished to
communicate private thoughts for CEA's eyes only--e.g., to complain
about a family member. Easy for Chapman to pontificate on "the purpose"
of their letters, as he did not have to regularly endure situations in
which he had absolutely no freedom to travel even short distances
without the indulgence of a male family member, was often isolated from
the sister she was so close to for extended time periods, and yet also
could not really write with total candor to a trusted sister who
otherwise would have discreetly kept secret what was written to her.
And, to boot, to have to worry about every word costing money. I would
imagine that this situation was sometimes a considerable hardship and
source of resentment for JA, and with good reason.

Which makes me wonder things like whether JA might have sometimes
slipped an extra small sheet into some of her letters to CEA, which
extra sheet would have been for CEA alone to read, with all the candid
comments, and might have included at the end something like what Lucy so
ungrammatically wrote to Edward: "Please to destroy my scrawls...." And
then CEA would read that slip, absorb its meaning and then set it
aflame, before bringing the rest of the letter to everyone else's
attention? Like Mission Impossible. ;)

Has this subject of the privacy, or lack thereof, vis a vis JA's letters
to CEA, been addressed well in one or more of the biographies or in
scholarly articles? I did a quick search and came up empty, except for
that Chapman quote, but I am sure I have missed several other comments
on the subject of the privacy, or lack thereof, of the correspondence
between JA and CEA.

It seems like a topic that would be of interest to a lot of Janeites.