There's a show on Nat Geo -- forget the name, maybe Wild Adventures?? Anyway, the guy has trained Brutus a 800 lb grizzly since he as a cub. Started a grizzly sanctuary in Montana and actually uses Brutus for film and testing products. A recent show had an introduction of Brutus with another grizzly. They actually seperated the grass area with two portable electric fences that created about a 10' clear space between them. That way they could observe how the two would react to each other face to face sort to speak without them likely becoming entangled. Only after observing the bears observe each other, did they remove the fence and keep their fingers crossed.
Needless to say, I wonder if the WSU folks did something similar.......   

If they didn't, I wonder if they could've seen some initial aggression being shown and stop the introduction at that point before they could interact within reach of each other....