Such a subtext is inherently offensive because it suggests that the recipient of the "compliment" is notably different from other black people.

"Historically, it was meant to signal the exceptional Negro," Mr. Dyson said. "The implication is that most black people do not have the capacity to engage in articulate speech, when white people are automatically assumed to be articulate."

This column by Lynette Clemetson in the New York Times is very eye opening for me -- I had not even thought about "articulate" as being patronizing in and of itself. For instance, when Joseph Biden offered his faint praise for Barack Obama (which is perhaps starting to look like a sad pattern of casual prejudice), I immediately focused on his use of "clean."

Clean? (That's the word Biden and Jon Stewart joked about on the Daily Show, too.)

I had not considered that "articulate" would be the most loaded word in Biden's lame utterance -- especially since Obama is the most eloquent of the Democratic presidential candidates in the race so far -- but there it is.