[Avodah] Ko Kayli, Hoshanos, and HaShem HaShem on Yom Kippur

[Zev Sero]

RallisW at aol.com wrote:
> Where did the minhog of reciting Ko Kayli come from? Why is it not said 
> on Shabbos which occurs on Yom Tov? Why is it not recited when on says 
> Yizkor (if one should say Yizkor on Yom Tov is another issue)? 

As I understand it, it's said to fill the gap between the haftarah and
ashrei, when nothing else is said then.  On Shabbos there's yekum purkan,
on the last days of yomtov there's yizkor, on Rosh Hashana there's the
shofar, on Simchas Torah there's sisu vesimchu.  So that leaves the first
two days of Pesach, the first day of Shavuos, and the first two days of
Sukkos, when they're on weekdays.

I've also seen in one siddur that on the first day of Pesach there's no
need for this piyut because of tal, and on the first day of Shovuos
because of akdomus, even though those don't come between the haftarah
and ashrei.  According to this, that leaves only the second day of Pesach
and the first two days of Sukkos, when they're on weekdays.

-- 
Zev Sero               Something has gone seriously awry with this Court's
zev at sero.name          interpretation of the Constitution.
                       	                          - Clarence Thomas