wouldn't it have been possible to use one of the old observer spells that reveal the whole map to clear the particles?
I'm not sure if that tool exists, but more importantly at the time of the crash we didn't actually know what was causing problems. If something like that did exist (and we understood the crash) this would have prevented it from happening.
In fact, when I was doing some testing on the fix and tracking cpu usage, I would spam spell sin fountain, see the server begin to slow down, then cast hawk shot with ashe and see the server improve