Anyone lubricating threads should decrease the installation torque a bit. That's because less of the applied torque is used at fighting thread-friction, and more get's applied to the actual joint, which could be bad on aluminum threads. If you plan to be in the camp that will be loosening and re-torquing these once per year, some anti-sieze on the threads might actually be good (with less installation torque...34Nm - 10% =~30Nm?). It would reduce the chance of aluminum galling from repeated torquing, and because you are checking at least once per year, there is little fear of the plugs loosening to the point of a problem before the next check. If the 30Nm concerns you, retorque them after a week or 2 (without loosening), and see if they move.
Hmmm......