Last night, I had a "duh" moment. To prevent spattering, and the smoke that comes from the resultant burning grease, simply add a cup or two of water to the pan bottome when putting the roast in the oven. This prevents any build up of hot grease that can cause spattering. Then, as the roast cooks, it will release some of its water in the form of flavorful juices, which again, prevents spattering. But you still have to raise the roast on a fack, or even on crumpled aluminum foil balls, above the water level.
Seeeeeeya; Goodweed of the North