Originally Posted by: guitarplayer196Chris:
Thanks for helping with the practical aspect of it - Your example shows that both myself and the original poster were actually both right but looking at it from the 2 different uses. In your first example, playing the A mixolodian mode over a song in D major, I understand it is the mixolodian mode but in my mind, I just equate it to D major, just starting at a different, non D root (In this case).
The ornamental use(which is the way I look at modes of being of value) is a bit more complex and how the lead guitar part will have its own distinct sound since we are including some notes that are not part of the major scale.

So now I can spend the year or so trying to master this.

as always, I appreciate your help.

The easiest way I became to understand it, and the trick to smoothly change keys within a song; is that if your playing a G Major chord, you can "get away" with soloing any of the G Major scale modes (Ionian, Lydian, Mixo). Same with Minor. If your playing an F minor chord, you can typically get away soloing with F Aeolian, F Dorian, F Phrygian over that F Minor chord.

Fm: F G# C

F Aeolian: F G G# A# C C# D# F (key of G#)
F Dorian: F G G# A# C D D# F (key of D#)
F Phyrg: F F# G# A# C C# D# F (key of C#)

As you see, in all 3 modes you are still hitting the notes that create the F minor chord while changing keys and as well as simply stepping out of the box. I know I stomped on modes, but I will admit I use the modes as a fast tool to figure out all the keys I can mess with that "support" a certain chord and an easy way to glide between different Keys.