Here's the post, quoted for your convenience.
However, I now have some headlining news that I'm suddenly getting extended pauses in the game to the point of unplayability. This is the first time there has been ANY hesitation in the game.
The extended pauses appear to be triggered by the Story Mode calculations. It seems the algorithms may be slightly computationally expensive, as instead of simply permitting any random shit to happen, an exhaustive scan is performed to make sure that the action is valid. The fact that it hits so hard is PROBABLY why EA threw together the half-assed system. We are looking into ways of reducing this impact.
I'm getting long pauses at 1am. Nothing that makes the game unplayable, as it passes within a minute or so, just a long hiccup where I can't do anything (though the Sims are still breathing, the plumbob still sparkles, etc.)
Yes, this is the chewing that the game is doing. Apparently, the game's "sophisticated" method of generating actions turns out to be "generate about a million possibilities of totally random, senseless shit, then throw pretty much all of it out and pick about 5". When the code was added to make it pick SENSIBLE shit, which is much more computationally intensive to generate, it thrashes.