I don't know The Grey Cock.

D Dorian D E F G A B C D
F Major F G A Bb C D E F
F Lydian F G A B C D E F


This singer sings a flat third for 'my dear love' at about 50 in. So that bit sounds minor.

https://www.8notes.com/scores/4735.asp

This also ends with a flat 3rd, major 2nd 1. That sound minor.

Haven't looked at the rest of it. For Lydian in with this 'tonal centre' wouldn't we need E – F# – G# – A# – B – C# – D#?

Too late for more thought on the subject. Too many ledger lines for comfort.

Brian: 05.23 Yes.