The following excerpt touches upon a point that has piqued my interest for the past few years now. Although the author, Brian S. Chan, does not deal specifically with liturgical ceremonies or worship practices, I believe that what he has to say does pertain to the diversities and controversies that have come to be the norm in those areas. From my reading, it is clear that Luther's views on music, in particular, coincide closely with the ancient and medieval understanding of beauty, such as Chan describes (drawing upon Umberto Eco):
"As Eco tracked beauty's definition over the centuries, he discovered the canon gradually became less popular. Society wanted to push beyond the canon. People wanted to define beauty according to originality, the surprise factor, the genius factor and the passion element. When Eco's research finally landed in our contemporary day of mass media and plurality, he concluded that a single idea of beauty no longer exists. Beauty could be whatever is pleasing, provocative, marketable or consumable. Beauty was defined by 'whatever sells,' fueling an overall superficial sense of beauty. He reasoned that if a time traveler from the future visited our present-day, he would 'have to surrender before the orgy of tolerance, the total syncretism and the absolute and unstoppable polytheism of Beauty.'
"According to Eco, beauty in contemporary time no longer had a unified definition. It's not surprising that the plurality of beauty reflects the plurality of spirituality as well. Tolerance that allows for multiple views versus an objective view of truth became the greatest virtue and definition of ideologies in our time" (The Purple Curtain, by Brian S. Chan, Chapter Two).