These guys are pretty amazing and you just know that every once in a while the separation drops to zero. Fortunately, at those relative speeds minor contact can be tolerated with little or no damage.
In 1985 I went out to Dayton Ohio to do some robot programming while working at IBM and during the weekend they had the Wright Paterson airshow that featured the Blue Angles. Just a few weeks before the show the Angles had an accident and one of them was killed so it was by no means certain they would show up and perform. They did, but one of the solo pilots screwed up and flew down the active runway, a runway still being used by commercial aircraft. Thankfully nothing bad happened, but even these guys can get rattled.
BTW, if you're ever in the Dayton area a visit to the Wright Pat Air Museum is a must. Perhaps the coolest plane they have is the sole remaining XB-70 -- freaking awesome.
Brian