Shit I agree with him. I'll likely never have a baby with a white girl and I'll likely never date, much less marry and have a family with one. Mixxed race babies grow taller, are more intelligent, and have better immune systems... Not to mention more attractive. So you have tall good-looking children who are intelligent and never get sick. Sounds like a recipe for Success if you ask me.
Compare that to the other end of the spectrum with inbreeding. Just take a look at the white folks and places like Ireland or Northern Ireland or England or the Appalachians in US, West Virginia and even blacks in the south and such. Didn't work out to well for them, did it?