The fundamental assumption is that the address only gets one payment.
That's a poor assumption given the discussion you were participating in:
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Hey Danny , very nice explanation and I understand it well until now but a question comes naturally to me because I always use the same addresses from my hardware wallet.
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If you screw with the fundamental assumption and hand out an address for multiple payments then I am not sure. I have never done that with my Trezor.
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Which is why I specified...
That depends on the wallet you are using, and whether that 2 BTC was received as a single payment or multiple payments to the same address.