Ray - the current thinking is that a little bit of thiosulfate left in the film/paper will actually protect the silver by forming a little coating of sulfide on the silver. Like sulfide toning, but at a greatly reduced amount. Hypo Eliminators remove all the thiosulfate by converting them to sulfate, which is easily removed from the emulsion. So it's believed that it's best to not get rid of all the thiosulfate, and so hypo eliminators are now not recommended.