The German organ tablature — both the «old» as well as the «new» one — has by its nature good capacities to represent the horizontal, contrapuntal part-writing «line by line» with high fidelity, like an open score. This feature would have to be of a great value for keyboard intabulating of the vocal polyphonic compositions. But the sources of the XVI–XVII centuries often show us the coexistence of the «score» principle (that of clear voice-leading) with the «tablature» principle proper (privileging the instrumental specificity and organist’s commodity). During this period, there have been substantial evolution of the intabulation methods and treatment of tablature as a notation form. While in the early 16th-century sources each tablature line usually transcribes a voice of a polyphonic ensemble in its integrity («score» principle), the later 17th-century and especially 17th-century transcribing methods become more varied and often freer. Sometimes voices of a polyphonic piece are transcribed in tablature lines literally (just as in earlier works), creating a kind of «letter score», that seems to be rather multifunctional than specifically organ transcription. However in many cases (probably in the most part of them), the genuine «tablature» principle, that simplifies (and distorts) written counterpoint in order to make it easier to read, to play and to copy, is preferred to the «score» method. There are, essentially, two kinds of simplifications: (1) rewriting of the passages, which in the original vocal work are written in crossed part-writing, in uncrossed form for the sake of easier reading and distribution between a musician’s hands; (2) reduction of number of parts, especially in works for six and more voices (polychoral works in particular). These tendencies have their extreme expression in such methods as recomposition of the whole polyphonic texture on the basis of the harmonic structure of the original work, or its reduction to just a two-voice frame (treble and bass).