I do not mean to impugn the good work of any of the women's religious orders--whether their members adhere to Catholic doctrine or challenge it. Nevertheless, over the long history of the Catholic Church, the Catholics who have done the most to help the poor have been orthodox.
Dorothy Day did more to help the poor than any other twentieth-century American Catholic. I have not read all her writings, but from what I have read, Dorothy Day never challenged fundamental Catholic doctrine during her long life of service.
Dorothy Day was an unqualified pacifist, and she sometimes criticized American foreign policy in her famous newspaper, The Catholic Worker. Her views made the New York archdiocese hierarchy uncomfortable, and in March, 1951, the chancellor of the Archdiocese told her she must cease publishing The Catholic Worker or change its name.
Robert Ellsberg records Dorothy's response in his annotated publication of her diaries:
Dorothy replied: "First of all I wish to assure you of our love and respectful obedience to the Church, and our gratitude to this Archdiocese, which has so often and so generously defended us from many who attack us. . . " She noted that none of the staff wished to change the name of the CW, which had operated under that name for 18 years. . . . While she stood ready to receive criticism or disciplinary censure for any theological errors,she noted that ceasing publication "would be a grave scandal to our readers and would put into the hands of our enemies, the enemies of the Church, a formidable weapon." She resolved to be "less dogmatic, more persuasive, less irritating, more winning." The matter was not raised again.(Ellsberg, 2008, p. 154, n. 124.)
When we reflect upon the saints--Francis of Assisi, Catherine of Siena, Teresa of Avila, Therese of Lisieux, Katharine Drexel, Edith Stein, Maximillian Kolbe--people who gave their lives to serve others in the name of their Catholic faith, I don't think you will find one saint who openly challenged fundamental Church doctrine.
Let's not let the secular media get away with portraying our Church's rebels as the good guys. Over the centuries, the good guys were the saints; and the saints did not spend their time wrangling with the Church hierarchy. The saints spent their lives in the service of others.
Ellsberg, Robert. The Duty of Delight: The Diaries of Dorothy Day. Milwaukee: Marquette University Press, 2008.
Goodstein, Laurie. Nuns Weigh Response to Scathing Vatican Rebuke. New York Times, July 28,2012.