Of course you can get some performance gain, but this is dangerous. If the latency is set too low the PC might not boot, then you will have to reset the BIOS.
You can try and lower it by small amounts then stress the processor and see if it crashes. And continue until it does then back it off a bit. Like I said earlier, if it crashes on boot then you'll have to reset the BIOS.
I don't see a need for this, but, hey that's what the BIOS option is for