I'm not convinced that many of the "dry taper" are actually degreasing the metal surfaces before assembly. Interference fits have a "less than zero" tolerance, any extra lubricant needs to hydraulic out of the joint, and I'm going to make a guess here, but the energy/torque needed to move the grease out adds a variable to the creation of an interference fit that relies on "stiction" Myself I make sure to wipe all the grease off the spindle before assembly, and will lightly grease and wipe clean a spindle that has been degreased.

Only data point I can realy add is that I while trying to free something up I got Triflow on the the left spindle of my assemble bike and then went for a ride. The left crank arm worked loose with in a couple miles. It had been a while since I had checked the bolts, but it had held fine with just the stiction.