i think you are misunderstanding me, i am referring to tunes that are in a mixolydian mode, for example banish misfortune a tune basically in d mixolydian, its starting point is a d major chord, because the scale of d mix has f# in it it is harmonised with a d major chord not a d minor chord. of course banish misfortune has other chords mainly c major and an occasional g major, I did not mentionthis because I THOUGHT IT WAS OBVIOUS.
but my point is that when the melody in the D mixolydian mode is an f#, it is not harmonised with a d minor, as some clueless session guitarists have tried to maintain, but a d major chord or a d dyad consisting of D and A, the first and fifth of the chord.
chords consist of a series of melody notes, for example tripping upstairs has a run of f#db, a b minor chord [broken up], sorry I do not mean to sound patronising, but a few guitarists i have met just dont seem to hear it.
tone deaf guitarists should take up hang gliding.