The school of John Glykys and his followers like John and Xenos Korones created the "Late Byzantine" system of round notation. But the use of just one notation system could seduce to the conclusion, that every chant genre has to be performed in the same way. Instead a huge number of different methods had to be observed, which were part of an oral tradition, sometimes even of a particular one which depended on a certain local school. However, the notation itself is sometimes not regarded as one system of its own, since it simply continued an already existing synthesis of many different notations (like the one of the asmatikon) within the notation developed in the monastic books of the sticherarion and the heirmologion. John Koukouzelis is also regarded as the creator of a new chant book which replaced the former books of the cathedral rite, the book of the choir (asmatikon), and the book of the lampadarios or monophonaris who sometimes replaced the left choir. The latter book was called "psaltikon" or "kontakarion", while the new book which combined the content of the older books, was called "order of services" () and these manuscripts are conventionally ascribed to John Koukouzelis. The Constantinopolitan redaction of the sticherarion and the heirmologion during the fourteenth century were often ascribed to John as well, but it was obviously neither the redaction of just one scribe, nor did the new kalophonic method intend any changes which contradicted the traditional ways. John Koukouzelis was obviously just one among a group of very talented musicians and reformers. Nevertheless, his legendary reputation caused that he is often identified with the reform itself. This identification is a common phenomenon in many Oriental and Andalusian traditions whose orally based transmission had never been completely abandoned.