I guess its a result of jockeys getting larger.

They really need to have a higher avg weight then and much higher then the 56 odd kilos at the moment. Make the average weight 60 kilos and the top weights get up to 65-70 kilos and then weight may once again become a major factor in handicapping.

15-20 kilos difference would be a good idea imo for handicap races between top weight and bottom weight.