Violet Alford's books, though interesting, are now rather outdated in their scholarship. A lot of better documented work has been done in the last 70 years which makes much of her commentary both redundant and misleading. See, for example, Mike Heaney's An Introductory Bibliography on Morris Dancing for references.

Historically, "Moors" were the peoples of North Africa. I'm not sure why an African American group would want to extend that to include all Americans of African descent, unless perhaps for ideological and/or religious reasons of their own.