In Kohelet 5:1 (Al Tibahel), Ibn Ezra has a lengthy, harsh critique of R. Eliezer HaKalir and other Paytanim for their poetry's components (in short: flowery language, the use of allegory/metaphor/simile, mistakes in Hebrew, the use of Aggadic material) and their insertion into prayer. However, the Rosh Hashana and Yom Kippur Machzor includes the statement beginning with "Misod Chachamim U-Nevonim" as a justification for inserting Piyyutim. Based on this, I ask the following:
1) Are there any communities that are strictly opposed to the recitation of Piyyutim in Chazarat HaShatz or for that matter in Davening across the board? (Excuse my ignorance)
2) When did the recitation of Piyyutim in Davening become the accepted norm, at least in Ashkenazi communities?
3) Can anyone recommend a work on the subject?