It's been said before, but I'm weighing in: in no way does this attempt at lag require a nerf of twf dps. That's obviously a separate balance issue, period. If TWF does more damage, it costs more: more resources (2x the weapons) more feats, more enhancements, and more stats (unless you go ranger, but then, rangers are designed for light armor boosted by dex, and have situational ranged dps which is also dex dependent. They also don't get strength enhancements to boost damage rolls.)
I'm new to this game, and was enjoying it enough to buy lots of points and lots of packs. It seemed like while yes, there's been plenty of FOTM's, since nerfed, there was no "right" way. But then I'm told that finesse builds are simply sad at endgame content, and that progressively everything has been trending to slot melee into first a nice, little str-based pigeonhole, and now, to one weapon only, since why on earth are you going to put that much effort into swinging two, and not come out at least somewhat ahead? I really thought this game was different, that balance wasn't some kind of endless whack-a-mole nerf-fest. I really hope I'm right, and I have one question i'm hoping can be commented on:
If speed increases are the problem for your engine/hardware, why can't you simply translate the attack portion of all haste/boost effects into additional attacks that are ALL piggybacked, without reducing damage? If you feel that TWF vs THF has balance issues, then why can't that be looked at on its own merit? Because if your goal is to make something that requires no trade-offs in terms of feats or stats equal to something that requires you to plan your entire build around it, that is manifestly wrong.
EDIT: Nasty thought, but while piggybacking physics checks is going to reduce the overhead a certain amount, there's no need to reduce damage in such a huge way unless your actual goal IS to push everyone to playing THF, which is half the weapons and weapon stats/effects to worry about. Say it ain't so, Joe.