Once upon a time, I rebuilt sports cars. For the record, they met the date limitation as "classic" for this list. I recall that greasing threads was taboo because it allowed you to over tighten a nut or bolt when using a torque wrench, resulting in deformation of the threads and increased likelihood of bolts breaking. Likewise, the logic against greasing the tapers on the bb--you could potentially overtighten the crank, deforming the soft metal of the crank. Of course, 1960s logic also said that you couldn't rotate radial tires left to right, but tire improvements make that a myth today, so I guess it is possible for there to have been studies that debunked the old theories about greasing things too. Since this is a classic list, I will stick to classic methods. It has worked for me thus far. Lou Deeter, "enjoying the 60 degree day in Monterey" Orlando FL