Does 'As a result, product proliferation represents a shift in the curve relating sales volume and variability (see Figure 7.4).' offer a contrasting position to 'Product proliferation has no effect on the curve relating to sales volume and variability.'
As a result, product proliferation represents a shift in the curve relating sales volume and variability (see Figure 7.4).###Product proliferation has no effect on the curve relating to sales volume and variability.