Serrations on the clamps is what keeps a saddle from nosing around, the screw only needs to be snug to do its job.
If you feel you really need to tighten that screw beyond torque specs, that's a sign to get a new seatpost.
Seaposts are really inexpensive. The elastomers in your saddle should be enough without the need of a suspension seatpost, which are also very heavy.