Not every council in the history of the Church has been a fruitful one; in the last analysis, many of them have been a waste of time. (In this connection, reference is repeatedly made, and with justification, to the Fifth Lateran Council, which met from 1512 to 1517 without doing anything effective to prevent the crisis that was developing.)...
...[W]e must be self-critical enough to acknowledge that the naive optimism of the Council and the self-esteem of many of its supporters justify, in a disturbing way, the gloomy diagnoses of early churchmen about the danger of councils...Despite all the good to be found in the texts it produced, the last word about the historical value of Vatican Council II has yet to be spoken. If, in the end, it will be numbered among the highlights of Church history depends on those who will transform its words into the life of the Church.
Principles of Catholic Theology, Joseph Ratzinger, San Francisco: Ignatius, 1987, 378.
"The fifth Lateran Council was closed in its twelfth session, on March 16, 1517. On October 31 of the same year Martin Luther nailed his ninety-five theses to the door of the court-church of Wittenberg." Ecumenical Councils of the Catholic Church, Hubert Jedin, New York: Paulist Press, 1960, 110.