I don't know what this author is speaking about - in South Florida 3/4 of the Cuban-Americans I know are white and of European ancestry with no inter marriage - some even with blond or red hair and kind of Irish looking because of their Galician blood which is of Celtic heritage - many are even descendents of the original conquistadors who came to cuba 500 yeras ago or founded St. Augustine the oldest "European" settlement in the United States.
http://www.babalublog.com/archives/piggyback.jpg
These are what typical white cubans-americans in Miami look like.
Honestly, who cares? The Latin American obsession with exact percentages of European ancestry is, in my humble opinion, stupid, racist and disgusting. The Argentines and Cubans are masters of it, but Brazilians (I know, not technically Latin American) and Mexicans are not far behind.
Yes, but Cuban-Americans, IIRC, have lower birthrates than other latinos, in fact I believe they are as low as Anglo whites. In addition, when Castro finally dies and Cuba becomes free, you may an influx of other Cubans who are of African descent.