I have not yet checked their ML approach. Regarding register updates you are right. I have also seen that they did only 10000 simulation runs to determine the

I have not yet checked their ML approach. Regarding register updates you are right. I have also seen that they did only 10000 simulation runs to determine the standard deviation to be 1.00/sqrt(m). I think more simulations would be necessary to get a confidence interval for the standard deviation that is small enough to allow differentiation from 1.04/sqrt(m).