Amazing how I've been playing this game since 2009 and just now I find out about this.
On my Gateway p7805u FX gaming laptop p8400 2.26ghz dual core/ 9800m GTS (at stock speeds):
before using -exThreads=3 -cpucount=2
fps on bechmark 1 = 25
after using -exThreads=3 -cpucount=2
fps on bechmark 1 = 32
I've noticed that the missions I've created (especially my largest one, which is a beach landing assault) loads much faster. Their is also no stuttering or a long pause when I'm driving quickly through a map in a car.
I haven't tried this out on my gaming desktop (AMD 940 Black edition 3.0ghz + 8600 GTS SLI), it's still in storage.
anyway...thank you for this. I'm not feeling brave enough to test it out with other "-exThreads=" settings.