This is a quote from the book "On Zero Confirmation Transactions" by Chris Pacia
...actually confirm, the retailer could just refund it. The patches actually got merged into the codebase but, of course, the usual suspects bitched and moaned about ‘encouraging people to rely o n zero confirmation transactions’ and the code was removed.

So basically a patch that could have prevented people from fraud was removed. And what’s rich is that some of the sam
e people who blocked the double spend relaying cite the above attack as a reason why no one should use zero confirmation transactions. Nevertheless, companies were able to accomplish the same th...
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