Shambles, I can only speak to my knowledge and experience of the US, but the majority of black Americans may or may not know about the "historical differences" being cited here between mumming blackface and minstrel blackface. The point I'm making is so many of them find such "historical" justifications of the continued use of blackface, to be a justification of the continued use of stereotypes that are extremely painful to black Americans.

An excellent recent gauge of how black Americans feel today about this subject, was the extremely negative reaction from the black American community to Spike Lee's film "Bamboozled".

To say that Spike (a black American director from Brooklyn) hit a nerve in his community is quite the understatement.