Thanks for the quick replies.

Summary - it is written and clear that on domestic flights, the allowance for a silver medallion is 2 bags 70 lbs each free of charge. Thanks Andy.

However, it remains unclear what the allowance is on international flights ex-Europe. Asia to US/ US to Asia, under NWA it was very clear -- silver (and higher) 2 bags of 70 lbs each free in economy. I still don't see this actually written down at delta.com ..... I just hate to have to argue with the ground staff but I do have the old NW rules printed out (travel on NW tickets).