I think Coleman is trying to say is similar situations, like when skyscrapers are built, they are designed for the highest possible wind rating expected over the next many decades. If this windspeed is reached, even for a 10/th of a second, it will remain upright. Worst possible situation- and no structural failure. Bridges are not made to these same mandates. Instead of being built to the "worst scenario conjured up in their lifespans, they are built to hold a certain load and flex up to a point, and restrict anything that would exceed that maximum. I remember crossing a bridge in New Brunswick of similar design to the failed one in Minneapolis. Coming the other way was an oversize load with some dam transformer, driven by a truck that could barely pull it. More than 12 axles on the load, and I had to slow from 90kmh to 20kmh because the vibrations were so severe on the bridge. Scary, very scary. And if that didn't pop rivets out or shear the bolts, then these are some of the strongest types of bridges built, hands down.

The Fraser River Crossing approach closer to my neck-of-the-woods had a fire on the approach trestle. Although the trestle was replaced a couple years back, it actually was more stable AFTER the fire in the 1980's.

The Mythbusters had a real interesting test on a steel bridge. On an episode aired last year, they had placed an actuator on an upright main beam, and made the steel flex to a point that they were not confortable in. Verdict, BUSTED.