Fig. 1. Here's a proposed agenda for experimenting with the relationships between dominant chords and dominant scales. The idea is simple: Take one dominant scale and "run it" into its three related dominant scales
(see The Dominant Species to see what these relationships are). Since these scales are related to the point of being nearly interchangeable, you can begin soloing with one scale over a progression and then end up using another. The left column indicates the scale or scales to use over the progressions in the right column; Steps 1 through 4 show how to "run" the C dominant scale into its three related dominant scales. See Example 1 for some applications. One of the advantages of this method is that it gets you to practice progressions that are commonly found in jazz, as opposed to running patterns around the Circle of Fifths. It's not complex, but do keep in mind that this whole chart represents the possibilities for the scales related to Edim7, only one of the three diminished 7th chords. Once you go through the possibilities for the other two diminished 7th chords, you'll have covered all progressions in all keys - and probably have discovered all kinds of new voicings in the process!