Mystery out of the Modes PT 2. Mixolydian and Dorian.

Right here is where I think I can simplify things a  bit. 

So after all this buildup, you don't really need to know anything about mixo except that is is a Major scale with a flattened 7th degree and is the most common "chord-scale" to use over a dominant or any functional V7 chord in a pop or jazz setting.

Major Scale on the left, Mixolydian mode on the right.

For this particular student anyway, that was a huge conceptual breakthrough, he didn't have to learn all the mixolydian modes....HE ALREADY KNEW THEM.  If you can play a major scale you can play mixo...EASY..