Prim Drift: An explanation?

So, probably everyone who builds will know what I mean by 'prim drift' but just for clarification:

I can build something, link it, ignore it for a while, come back and all the prims in the link set have randomly shifted themselves around, sometimes as much as .03m out of their original place. Doesn't sound like a lot, but any builder knows that'll make a build look like shit in a heartbeat. Cracks everywhere, texture fighting, it's ridiculous. I have to realign it everytime I want to change it, and in the meantime I get to watch it fall apart for no reason at all. Why does this happen? I can buy 'rounding errors' for it moving fractions of that, but this is just plain silly.

Does LL have an explanation for this? Is it a 'known issue'? If it is, why is not a high priority to fix? This undermines the very foundation of what SecondLife is (user created content). Seems like this should be higher on the priority list than enabling players to make flopping prim dicks in preview.

One of the classic threads on this, where Andrew posted, is:I haven't run into the latest occurrences, but by all means, I'd like to know what's happening here so I can draw wider attention to it. If you could start a thread in Technical Issues please to get responses with more details, and best of all, if it's possible--a solid repro--I want to "mirror" it and set a build out for a few days as you describe and see the numbers shift around.

Sounds awful what's happening... currently I don't know of an Known Issue we have on the table about it; certainly would be a priority if it was, as you state. I hope an old problem hasn't resurfaced.

Best,