Pilots have been flying UNDER the Mackinac Bridge ever since it was built.
I have heard stories like this for 30 years.
Pilots have been flying under bridges all over the world ever since mostly reliable planes came on the scene.
See barn stormers, wing walkers, etc.
Now if somebody did it with an SR-71 or the Spruce Goose, THAT would be exciting.
Ive heard those stories, too. I remember all the backslapping at the Pellston airport when my father landed. My father flew A-6 Intruders in the Navy and T-38s for NASA. At least he knew what he was doing.