History of Patriarchal Tradition vs. Parish Tradition

This is a topic I have had some thoughts and questions on for quite some time. Many of the Patriarchal Chanters have compositions that would be considered entirely outside the Patriarchal Tradition. A specific one is the 3rd Mode trisagion hymn composed by Grigorios Protopsaltis. When I had asked about this piece on the old byzantinechant email list Mr. Dimitri Koubaroulis informed me it was composed for Parish use. I also have heard this was the reasoning and justification of why Pringos and Stanitsas composed and performed their experimental Maqam Leitorgika.

So, what were the differences between Parish and Patriarchal Tradition? From my observances it seems that different mode Trisagia and Leitorgika were completely allowed in parishes, and even encouraged.

A few other questions:

  • Why did Patriarchal chanters not do more to promote the Patriarchal school of chanting in the choices of the pieces they performed when in other parishes?

  • Why was the Kliton Anaphora abandoned by Pringos and Stanitsas in favor of experimental maqams and multi-modal (Deuteroprotos) for Leitorgika in parish settings?

  • How does one "interpret" these exceptions nowadays? What is allowed in parishes? Are complex and multi-modal Leitorgika proper to sing in parishes? What about different Trisagia?

A good resource and reference for these different compositions is http://cmkon.org/Keimena.htm#ΑΓΑΠΗΣΩ ΣΕ