While there is abundant evidence that the molecular weight distribution (MWD) of a linear polymer has an influence on the shape of the viscosity function, the ability to convert the viscosity function to an MWD has been questioned. Using strictly numerical techniques, we have shown that the viscosity function can be transformed to the MWD, but always with some distortion. However, distinct bimodality can be qualitatively preserved through both the MWD-viscosity and viscosity-MWD transforms.