There is where all the talk of "binding" comes from in poly bushings.
Factory torque specs are for rubber bushings!
If you tighten aftermarket poly bushings to factory specs you will more than likely have problems with the bushings making noise or actually cracking from being to tight.
Suspensions are supposed to work "freely" with the least amount of resistance.
There is really no magic number. We generally tell customers to tighten to just under factory specs and work the component by hand to assure that it works freely.
It should have some resistance without the weight of the car on it but not to the point it doesn't move freely.
This will get you in the ballpark of what the torque specs should be.
Final tightening of components should be done with the weight of the car on everything either by having the car on the ground or compressing the suspension if it is on a lift.
Locking nuts should be used on all components so there is never a chance of anything coming loose.