dahs, I more-or-less agree with your position.
However, the one thing that you don't have the benefit of is HD experience, so you're not familiar with the fact that WIS has a track record of making changes, etc. and not informing people. Historically, they really can't be relied upon to disclose things to us. That aspect is definitely better under seble, but if this is a long-standing feature, it is totally plausible that it has existed and not been communicated.
Again, I don't believe there is an extra randomness factor. But the notion that they would definitely tell us if it existed is not consistent with WIS's general pattern of behavior.
Also, you should know that seble (the admin) has openly admitted that there are flaws with the current engine, and they are working on fixing those. So at this point, anyone who maintains that the engine is working exactly as intended must also believe in the Tooth Fairy and the Easter Bunny.
(That said, while there are obvious flaws in the sim, it's also abundantly clear that many of the examples of something not working brought up by colonels and others are not really good examples.)