This is a classic display of what I call "The Dominant Spider". Palm down gestures are always taken as dominant and overtly authoritative. Audiences receive them considerably more negatively versus palms up displays - even with an audience of one (Pease). Although gesturing with your palms down is not as negative as pointing - it should, in most cases, be avoided. This display of The Dominant Spider by the late Libyan Dictator, Muammar Gaddafi (Moammar Gadhafi) - while a bit more subtle than Khrushchev banging his shoe, is an example of a gesture I will coach-out of most people.