Is There a Difference Between Hard and Soft Universalism?

In an article in Church Life magazine, Rooney distinguishes between what he calls hard universalism and soft universalism. He says pretty universalism is that it is impossible for anyone to go to hell forever because it is necessarily true that all shall be saved. Then you have a non-horetical view he calls soft universalism, which he associates with Jacques-Mary Tan and Hans-Wirce von Valtasar. So it is compatible then with the Orthodox position where we can't know if all will be saved.