I'm not quite sure i follow the difference between a complex mixture of polypeptides that may have batch to batch variability, and a complex mixture of sugars like lovenox that has batch to batch variability. if anything characterizing a mix of polypeptides is easier than sugars, and any manufacturing process will have to have variability that is within parameters as branded product (or better - i.e. less variability and more homogeneous product between batches)