No conclave since 1830 has lasted more than a week.
The past eleven conclaves, going back 167 years, have averaged 3.5 days with no conclave lasting more than 5 days.
The longer conclaves that proceeded the 1846 conclave were generally longer not because they were "more prayerful" but because various monarchs did their best to intrude on and game the proceedings.
These long conclaves were characterized more by acrimony than meditative prayer.
If this conclave lasts more than 5 days, it is not necessarily a positive sign, nor is it an indication that the cardinals have been more prayerful than their colleagues in the past who - after brief deliberations - gave the Church Blessed Pius IX, St. Pius X, Blessed Pius XII, Blessed John XXIII and Servant of God John Paul II, as well as Benedict XVI.
I would be surprised if it goes beyond 7 days myself.
Got to remember that we are now in the middle of Lent, early Easter this year and those same cardinals want to get back to their home countries for the events of Holy Week/Easter.
But at the same time too, remember the last conclave lasted only a day and I sense that B16 became Pope only because Blessed JP2 from his death bed asked him to take the honor, but that is me.
I do not know if there is any info on this but was there a conclave during the middle ages that went so long that the people of the time got fed up and ended up storming the location just to demand there be a new Pope?
The ones I really get concern are the “curia insiders”.