Many have a custom not to say the Shir Shel Yom or Ein Kelokeinu on Tisha BeAv morning. Why not?
I have seen in many siddurim, mainly in korbonos, the phrase "if you have time, add this parsha". How do you know if you have time? It seems obvious that if adding it would make you miss zman ...
Do you have to say korbonos? If so, why is it not said with the shaliach tzibbur?