Thanks for your comment. Almost everyone I spoke with was also incredulous that much oil could be consumed due to a defective PCV valve.
Imagine what went through my mind after starting the trip with the oil at the full mark, then at the first stop at 400 miles finding no oil on the dip stick at all. Then having to add 3 quarts to bring it up to full. The crankcase only holds 5.
But the only two things done to the van after arriving in Seattle was to have the valve cover removed and replaced, and the PCV valve replaced. So go figure . . .