Hello, Allen! If you are asking me if I accept the notion that enslaved African Americans learned how to tap dance while they were on the horrorific slave ships, I would respond with one word "NO".
However, I do believe that there was eventually an exchange of dance information and styles between African Americans and other non-African peoples.
It's just MUCH more complicated than that..
I would suggest these books on African dance:
Kariamu Welsh Asante, editor "African Dance; An Artistic, Historical, and Philosphical Inquiry" {Trenton, New Jersey; Africa World Press, Inc. second printing 1998}
Omofolabo S. Ajayi, "Yoruba Dance, The Semiotics if Movement and Body Attitude in Nigerian Culture" {Trenton, New Jersey, Africa World Press, 1998}
Lynne Fauley Emery, "Black Dance from 1619 to Today", second revised edition {Princeton, New Jersey, Princeton Book Co., 1988}
Also here is a book on related topic: Sussana Sloat, editor "Caribbean Dance from Abakua to Zouk: How Movement Shapes Identity" {Gainesville,University Press of Florida, 2002}
In addition, see this excerpt from the anthology "African Dance" "..there are many styles of dance in Africa, as numerous as the different ethnic groups...Dance is a way of life for African people and is associated with everyday activities. Dances can be grouped into categories such as birth, death, puberty, war, recreation, initiation and ritual. Dance in Africa is always accompanied by music which ranges from handclapping and singing to massive orchestras of of instrumentation. Dance is so vital in the everyday lives of people, that in Ghana if you are a chief and cannot dance the way of your people, you can be dethroned. Dance is Africa is a way of life, a source of communication, and history reenacted through movement." {"Traditional Dance in Africa"; p. 26}