Increasing the margin requirements will not discourage buyers of real silver. The COMEX contracts are just a down payment if you plan to actually take delivery of bullion, and so the fact that you can capture less leverage due to higher margin is neither here nor there if you are going to post the full purchase price. Retail spec shorts are also going to be driven away from the paper market by raising margin, and this will just serve to further concentrate the net short interest among the big banks that can afford to carry huge losses and post big margin reserves.

cheers!

mike