I, too, always vindicate Sophie against many of the accusations made against her, but what always anoys me about Praschl-Bichler is that she keeps arguing Sophie and Elisabeth had the best of relationships until the archduchess died, and that everything negative Sisi said about Sophie afterwards derived from Elisabeth projecting the difficulties she had with her own mother on Sophie. This is all conjectural psychologising, and to me it's not at all convincing.
The sources give a lot of hints that Sophie did actually like Sisi, that she was never against Franz Josef marrying her. In this Praschl-Bichler is right. But this isn't news at all. What they do not prove is that Sisi liked her mother-in- law likewise or that what she writes about her is all made up.
The two women simply had different characters and different ways of looking at things. Elisabeth was certainly being unfair in the way she criticised Sophie, and she never questioned her own, often very selfish, ways, but this doesn't mean Sophie was the great mother-in-law of Praschl-Bichler's imagination.
Gabriele P.-B. likes to cite mainly from Sophie's letters and diaries, but she doesn't look at more disinterested sources to compare and reach a more balanced view. Her method doesn't meet the requirements of scholarship. She just doesn't present the necessary evidence.