They do, but the way its setup now adds spring force with increasing throttle. So it acts as a 3rd throttle return spring. Depending on the driver, that may be a bit much.
As far as the last spring, all it does is counter the throttle return springs.
You want to say the OP's setup will do the job, or that I'm wrong, that's fine.
As far as your insults go, they are uncalled for.