Brian Marick has some good strategies for figuring out most of the business-level details that your customer wants you to solve.
One example: People should ask questions about details. If the business expert casually says, "So we have a cow in stall 1", ask why it's in stall 1. The answer might be, "well, actually, it probably wouldn't be in stall 1, because that's the bull stall" - which now alerts everyone that there are rules surrounding which animals go in what stalls. Those rules might not matter soon, but it doesn't hurt to be aware of them.
My name is Reinout van Rees and I program in Python, I live in the Netherlands, I cycle recumbent bikes and I have a model railway.
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