Poetry in the prayers – Ask the Rabbi
Q. There are so many difficult poems in the High Holyday prayers. Must we say them all?
A. The liturgical poems are piyyutim, from the same Greek origin as the English “poet”.
Not every community adopted the same piyyutim. Some rabbis strongly opposed piyyutic interpolations as an unwarranted disturbance of the flow of the service and because the piyyutim were often too abstruse and complicated.
The Chafetz Chayyim was not too wedded to saying all the piyyutim, and some communities published their own lists of piyyutim.
In Britain, the Chief Rabbis Adler sanctioned revised lists of piyyutim which became standard in the Anglo-Jewry. Some piyyutim, though their exclusion was permitted, remained so popular that they were retained regardless of rabbinic rulings.
The short answer to your question, therefore, is that there is no statutory obligation to say all the piyyutim, though many people would feel cheated without them.