It's called Admixture, the same reason Obama can pronounce words. His facial features still show he's not white though. He looks like a mixed race person with negroid facial features to me albeit more caucasoid than some blacks.
Do you think pure Blacks have genetically inherent inability to pronounce western tongues ?
I took a speech class, and the black speech instructor tried to speak properly but still ended up slipping into ebonics sometimes. She even said that the shape of people's mouths and throats, which vary by ethnic background, influence people's ability to speak and pronounce different syllables.
Some can learn how to get around this, but its inherently more difficult for them.
Obama sometimes slips into Black accents
Obama does that because he is a chameleon.
This is something I have found true of many people of mixed background, whether it is racially mixed or ethnically mixed (like me).....my mom was an Italian Jew (by conversion and crypto ancestry), but her family was, for all intents and purposes, "regular" Italians.
My dad's family were "regular" Jews.
I grew up around both, and I used to notice that when I was around the Jewish side of the family, I'd "talk Jewish". When I'd be around the Italian side, I found myself "talking like an Italian".
I don't think its intentional, its just something that those of us with dual backgrounds tend to do, because, after all, we ARE "both"!
I've also been known to use a stream of epithets when I'm angry, that is a mixture of Yiddish and Italian!
I think Obammie does the same....also, he doesn't "feel fully black" because he was raised by Whites, and that gives him a certain sense of insecurity when he's around full blacks (I know because I feel that same insecurity when I'm around "full" Italians" or "full" Jews.)
(Oy madon, it sounds like I'm defending Obama...I'm not!)