re: There is very little difference betwen the two, considering what happened in between!
I think damage like that under constant stresses increases exponentially, as the area increases. It looks as if the surface of one of the tiles is starting to crack further, for instance.
I know from having been in sustained high winds that once something disrupts the flow the wind just worries and worries and worries at it until it gives. AND, that's not with the Shuttle materials and at those speeds and temperatures. Might be different.
Arf