Speculators on the floors of commodities exchanges have been called many things, but sensitive, or solicitous of the interests of public investors, are not among them.

So it shouldn't be surprising that one of the ways they have of profiting from the passively investing public is called "date rape". In the pits, physical or electronic, that means betting against the certainty that commodity index investors' positions are rolled in a mechanistic manner every month, in known patterns on particular days. The phenomenon could be called index roll congestion, or some other euphemism, but as we noted, these are not people who worry about your feelings.