If we hadn't been late getting out the door. If we had been a little *more* late getting out the door (so that I'd have seen the multiple DMs, which would have tipped me off).
There's a name for this in security circles: "Swiss-cheese security." Imagine multiple slices of Swiss cheese all stacked up, the holes in one slice blocked by the slice below it. All the slices move around and every now and again, a hole opens up that goes all the way through the stack. Zap!
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