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I first read this on p 94, but it looks like the same as p. 98 in 2015 edition that you can download.
I asked another question about point 4 in this passage, but with this question I am specifically asking about the following statement:
I know it sounds bizarre, but the system cannot seem to distinguish between having credit and using credit.
I don't know much about computers, but is it true? With all this technology, why can't they distinguish?