I seem to recall one of the DEV's long time ago perhaps it was Wilki or someone saying that the RNG was broken..... and they were working on fixing it...
Far as I can recall it was never "fixed" ..... and wasn't long thereafter that the DEV who said that was canned... If I remember right it may have been between the move from Austin to Cali... but I am not sure exactly.
It was Draconi.
He found out after me and several other people did some testing that the RNG was broken in a way that they weren't checking for.
The usual way to check to see if an RNG is flawed is to take a few million samples, and see how they reflect the spread. After all, the larger the sample, the randomness evens out the bumps to where only real problems stick out. BUT...
The issue that the RNG has is that it is prone to streaks on SMALL samples, and those streaks THEMSELVES are evenly distributed. Most of you know the kinds of streaks I'm talking about; Where you make 5 5% chances for success in a row in combat or crafting, or fail 8 times in a row on smelting an ore you had a 90% or 95% chance of success on.
Since the small-scale streaks were equally likely at ALL points of the distribution, they didn't show up on those 500,000, 1 million or more sample tests they were running. because the streaks were balanced out by other streaks at that scale. He said the RNG as it was/is was a public domain RNG of a type often used in mid-level computer programming classes as an assignment to rewrite from scratch, or a variant thereof. In fact, it was little different from the simple RNGs used by many Facebook games, simply because you don't have to pay for that class of RNGs.
Draconi began working on a replacement RNG on his own, and from the way he was talking was about a week or two of bringing it in, and starting internal testing of it, when the post-KR downsizing hit (possibly part of the California to VA move) and he was let go. As far as I know, It never got to the point where EA above the UO team level even knew of it, so Draconi's successors probably didn't even know about what was being referred to when we started asking the Mythic (and later, Bioware Mythic and Broadsword) teams what happened to Draconi's project.