Hitchcock's Definition of Incidental Business

I completely disagree with Hitchcock in this case I think that yes if you're a good enough filmmaker if you're Hitchcock you can have McGuffins so that the audience doesn't really care about and still just get people ramped up in the story anyway. props are the director's key to the design of incidental business which means things that the people are kind of doing in the scene like washing dishes right or chopping a meat for a sandwich unspoken suggestions for behavior that can prevent theatricality.