I'd say keep your reported balances below 10%, don't go out and grab a bunch of new credit, and don't be late anywhere else--and you've got as much of a chance of avoiding the dreaded FR as anyone else.
Judging from everything I've read, some FRs are totally random.
Of course, that's an inconvenience "up with which I would not put," and I would tell them if they're going to probe me space-alien style, they can have their card back. But that's just me.
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in a credit-scoring postnuclear Stone Age...