Do you have evidence that this is a fact? Have you looked at the computing requirements documents for, for example, stock exchanges? I have it on good evidence that stock exchanges ran on mainframes. They are essentially the counterparty (in a computing sense not a financial sense) in each placed order. If someone is willing to run a fiberoptic cable from Chicago to New York or New Jersey to exploit reduced propagation delay, admittedly much larger than a refresh stall, wouldn't you think that they or someone else would also be interested in predicting computing stalls. An exchange would face at least a significant reputational risk if it could be exploited that way.