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by mattclarkdotnet 83 days ago
At best it’s checking available credit. All the other stuff is done after the fact. The idea that any banking transaction involves “subtracting one number from another” is so wrong it’s barely worth engaging with.
2 comments

You speak so confidently, yet it appears you’ve never gotten a text asking you to approve or deny a charge that you are performing.
Some (rewards processing) is probably done later, but the fraud check definitely isn’t.