As Ghrumpy notes, "to grease or not to grease" has implications on the optimal torque. Huge machine tools use clean, ungreased ROUND tapers to hold cutting tools, and in many cases these machines are putting 25 or more horsepower into the tool - far more than legs put into a crank arm.

With my old Campy crank arms, I used ungreased taper, ungreased bolt and it worked fine and held the things on for many years. I think greasing the bolt, or using medium loctite, would be better. But again, the optimal torque should be different depending upon whether you have lube on the taper and/or the bolt.

Here's a large shell facing mill that has what is known as a Morse Taper (MT 7, for those interested):
http://www.algebra-inc.com/namedpic/...rbor-15679.jpg