Originally Posted by DMF
I use torque wrenches where necessary, and I use grease/oil/anti-seize where appropriate without adjusting the torque settings. Torque is almost never specified "dry"; the default is for 30W motor oil. If you're worried about it, then set the wrench for the low end of the range when using oil or grease.
Also, for using anti-seize instead of oil, the materials are much important that the location. Titanium for instance should always use (nickel) anti-seize. Aluminum usually (copper) anti-seize.
Torque specs are definitely for dry contact, without any friction modifiers in the threads. That is the only way for the fastering torque to track preload tension (or more directly, bolt elongation) correctly. The moment you introduce oils, grease or any other friction modifiers in the threads, that torque vs. preload curve is no longer linear. So even if you "derate" the spec'd torque using grease or oil, it's difficult to hit the spec'd preload tension just right.
There is another reason not to use grease. Again, grease is mostly oil thickened up with soap or some alkyline compound like lime (not a chemist). Problem is, over time, that oil might dry out, and you end up with a residue that don't offer much galling protection.
Anti-seize compound OTOH use metal compounds that are designed to offer a barrier layer even when all the oils have disappeared, particularly for high temp applications. The choice of different anti-seize compounds have more to do with that temp rating than the particular type of metal alloys. Nickel-based anti-seize is rated at much higher temp than copper-based. Since Titanium fasteners are most commonly selected in extremely high temp applications, that is why nickel anti-seize is often used in concert with Ti.
As I said in my earlier post, I agree with you and chunts that, with aluminum, using grease is better than not using anything at all. Most people tend to over torque, so given that situation where preload tension is not gonna be in spec anyhow, it's better to prevent galling.
It's the lesser of two evils.
Since the OP is asking to "make sure he does it right". I would strongly recommend anti-seize and a torque wrench.