Yes I too found it a bit S&M and dualistic. Still it portrays in sharp contrast the predicament of life in the modern world. there are Shades of Grey also, one doesn't have to choose between the two. In fact resolving the dichotomy of paradox seems to be one of the ways toward spiritual advancement. The work anyone does toward this must have an effect. The shock value of master-slave language and the choice between dualities as being absolute grabs for attention and comment. Sex has always sold and it works just as well in philosophy as it does in laundry soap.