This is a quote from the book "On Zero Confirmation Transactions" by Chris Pacia the face of overwhelming empirical evidence to the contrary.

So why haven’t miners rushed to adopt this “profit maximizing” policy? Well maybe one reason is that it isn’t
actually profit maximizing. The theory outlined above seems to be unduly focused on short run profits and not the overall health of the bitcoin ecosystem which is necessary for maximizing long term profits over the life of their mining investments. Blowing up zero confirmation transactions to the point where retail stores stop accepting Bitcoin, while simultaneously enabling rampant f...
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