B7, Em7, A7, Dma7 is simply a cycle of 5ths. Nothing more or nothing less, in key or out of key, regardles of quality of chord. Understanding where the dominants come from is the key to success. Otherwise, I agree for the most part. There are, to me, 2 chords I or i,a place to start, a V, a place to go to, and a i or I, a place to end. There are many variations, but it stills boils down to I or i and V.

"The Lydian Dominant is also a Mixolydian with a #4(just a note)." This statement is simply untrue. I've been trying for hours to make it true or to fit the rules. You can come close to lydian dominant by altering the true Dorian with a #4, not Mixo, this becomes a Dorian #11 or #4. (A maj scale is the dorian to B, another way to say this, is B is ii in the key of A or 1 whole step below the root.) You can also play A melodic minor, this gives you a Dorian b9 or combine both. This confusion always arises from not understanding mode construction. A mixo #4 conflicts with our example of B7. Not a dominant 7th, but a maj 7. Dorian is always ii except in Harmonic minor.
iv in Harmonic minor. There is no true mixolydian in Harmonic minor. Lydian Dominant and Mixolydian #4 are distinctly two different scales.

[Edited by griphon2 on 02-09-2003 at 05:14 PM]