Q. If [reciting piyutim – see earlier question] is based on the fact that few understand the language and meaning and that their time could be put to better use, why are we still saying the piyyutim we do say? Why are we still saying Selichos and Kinos? And why are we still reading the Haftarah, the majority of which are from Neviim Achronim and the Megilos Shir HaShirim and Koheles?

A. Reciting piyutim is a minhag, albeit, an ancient one (see Shir Hashirim Rabbo 3,10). In principle a “person should not deviate from the established minhag” (Baba Metziah 86b), however minhogim vary from one individual and his ancestry to his neighbor. Two psukim are quoted by the Poskim as a source for not digressing from ones minhag; “You shall not pull back your neighbor’s landmark, which the earlier ones have set as borders” (Devorim 19:14) and; “Hearken, my son, to the discipline of your father, and do not forsake the instruction of your mother” (Mishlei 1:8), they both emphasize the individuality of minhogim.

Reciting selichois and kinois is also a very old minhag, (See Rosh Hashono 17b and Divrei Hayomim II, 35,25). Reading maftir, however, is a rabbinical enactment or takono (see Megila 21a). The reason for this enactment is mentioned in Avudraham and in Bais Yosef (O.C. 284). Some opinions consider selichois as part of the tefilah (see Harerey Kedem p.18, quoting the Lebush). Kinois, at least according to some contemporary Poiskim, could still be written and added today. (See an ample discussion on the topic in Ohel Ysochor p.83)

Poiskim deal with many shailos and questions in regards of changing or modifying a minhag in times of need, as in when the Minyan will disintegrate, or when different groups with different minhogim join together etc. (see Igrois Moishe O.C. 2:21, Shevet Halevy 6:59, Oisrey Lagefen 27, et. al.)

Oitzer Minhogey Chasidim, (p.194) who strongly advocates the reciting of piyutim, writes;
“In our days, the custom of saying piyutim has spread to all Ysroel, every congregation and congregation according to its own tradition, Sephardim, Ashkenazim, Lithuanians and Chasidim. Some say all piyutim… some say only a part, some say the long ones, some omit them, everyone according to his tradition. There are some Chasidim that shorten their recitation during davening, but sing them later during the Yom Tov Seudos…. and on all of them, it already has been said; “Nahara nahara ufashtey”. (Chulin 18b, 57a), there are many rivers and each one has its own way of flowing”

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a