I've been looking into this business of Cassandra cutting up and destroying JA's letters or parts of them.

The most interesting account I have found thus far is to be seen in the Introduction to Jane Austen's Manuscript Letters in Facsimile written and edited by Jo Modert.

It would appear that the delicate sensibilites were nto Cassasndras,but were held by the next geneation of teh Asuten faily; thsoe nephews and nieces-Caroline ,Fanny, Edward Austen Leigh, who started the "controling" of her image which had been begun by Henry Austen in his biographical notice attatched to teh posthumous edition of Persuasion and Northhanger Abbey.

Let me explain futher.

If we look at one of Cassandras last letters to Charles Austen,detailing bequests in anticipation of her death,we can see that she does not ask for papers of JAs to be burnt etc.,etc:

Chawton May 9th

My dearest Charles

In a fromer will I had bequeathed all my Papers,Clothes & Trinkets to Martha to be disposed of by her according to my directions.Her Death obliges me to make a change in this Disposition of my effects:& in a Will which I have this day executed ,I allow all these articles to go to you as residuary Legatee; in the fullest confidence that you will attend to my wishes on teh subject as implicity as I am sure Martha heself would aheve done had she survived me.....

As I have leisure ,I am looking over & destroying some of my Papers- others I have marked " to be burned", whilst some will still remain. These are chiefly a few letters & a few manuscripts of our dear Jane, which I have set apart for those parties to whom I think they will be mostly valuable...

I think that last papragraph makes it quite clear that Cassandra has only destroyed, and asked to be destroyed, her own. papers and not those that related to JA and which were in her care.

Jo Modert then quotes from a letter from Caroline,LAdy Knatchbull( JAs neice) to her brother James Edward dated July 1871.Lord Stnahope wanted the family to publish JA last verses-written at Winchester on the 15th July 1817, three days before she died.They were funny and about the Winchester races and St Swithin and his curse re 40 days of rain.

The prospect of publishing them seems scandalous to CAroline.

My dear Edward,

I received yesterday from Anna yr dispatch to her& I dare say you wish to have copies returned of Ld Stanhopes letter & your s to him.-thank you so very much for the sight of them.I am sorry that Ld S should be raisng a hue and cry after these "lines replete with vigour and fancy" to which unluckily Uncle Henry alluded more than half a century ago- nobody felt any curiosity about them then- but see what it is to have a growing posthumous reputation! we cannot keep anything to ourselves now it seems...tho' there are no reasons ethical or orthodox against the publication of these stanzas, there are reasons of taste.-I never thought there was much of point to them- they were good enough for a passing thought,but if she had lived she would probably have torn them up- however there is a much stronger objection to their being inserted in amy memoir, than a want of literary merit-If put in at all they must have been introduced as the latest working of her mind...Till a few hours before she died,she had been feeling much better & there was hope of amendment at least , if not of recovery..but the joke about the dead saint & the Winchester races,all jumbled up together, would read badly as amongst the few details given of the closing scene

In another letter Caroline wrote:

...her letters to Aunt Casaandra were I daresay open and confidential-My Aunt looked them over and burnt the greater part(as she told me) 2 or 3 years before her own death-She left or gave some legacies to the Neices- but of those I have seen, several had portions cut out_

So Caroline is not really repeating what Cassandra had insturcted in her letter to Chsrels Austen, is she? From her letter we get teh idea that Cassandra had burned and was planning to burn more of her own. letters but had carefully set aside JAs letters to be preserved and handed down to the family.

As Jo Modert states:

it is hard to beleive, in fact, that Cassandra burned or destroyed anything bearing her sisters handwriting after seeing some of the scraps contained in the cache of papres preserved in the Charles Austen family

Introductino,p xxv.

So I am not sure we can blame Cassandra for any ommissions any more.Who is to blame, I cannot say either,but I dubt teh blame lies with Cassandra.