Just quick report.
Had a direct flight scheduled SLC to MSP. The fare was limited to certain connections including I think ORD and CVC only. Direct was 700 miles. Called and did a same day change via IAH for 2200 miles and snagged an upgrade for good measure.
Even if Silver many would consider that worth while at $50 with a additional 1500 miles at 3.3 cents a mile.