You are asking a question concerning how long it takes for such statistics to stabilize to steady-state values. That calls for dynamic statistical analysis and not static, steady-state analysis. The more I read the posts on this thread, the more convinced I am that the problem and the apparent observed variability, is an artifact arising from the fact that your runs simply have not been long enough to stabilize the statistics. I thought I saw you say in another post that you had gone two or three runs. Two or three hundred failures would be more like what you need, if not two or three thousand.
Masters degrees are something alltogether different.
Everyone benefits from that. It's a good question. I was thinking of doing a handful of runs and finding the earlist point at which they diverge. In my particular case, I suspect it's somewhere between 0 and 30 minutes. As soon as you try to back your thaumatology with equations, you lose the attention of most of the people who are developing tests today.