Campy will respond with the company line - follow the instructions. As a mechanical engineer, I use my own knowledge of threaded assemblies and ignore Campy.

I've read 3 to 4 different bike forums every day for 10 years. I've read about every problem you can imagine. UT crank complaints are fairly frequent and nearly every one can be explained by improper installation.

Campy instructions are notoriously bad. Not being able to read Italian, I don't know if it's a translation problem or just a poor technical writer to blame.

The fact is, you can only have one thread locking product in use at one time. Earlier instructions mentioned the locktite method, only as a second-rate method for those who did not have their BB shell faced. If the factory thread locker is not removed, that alone creates so much friction the you could never thread the cups in by hand, but Campy fails to even mention removing it. I've seen 10-15Nm of torqure required, just to overcome the thread locker friction. Loctite states that the threads must be clean and free of other materials, or the loctite will not work. Maybe Campy expects mechanics to read the loctite instructions. Removing all of the Campy-applied material probably requires a solvent, like lacquer thinner or acetone in addition to some aggressive brushing.

If the bearing cup faces are not fully seated against the BB shell, that effectively lenghtens the BB shell and could create an excessive bearing preload. Even if I did use loctite, I'd apply a little torque to be sure the cups are seated. The idea of not using any significant torque follows the assumption that the BB faces are not square to the threads and applying any torque could misalign the cups. There is no good substitute for having the BB faces square to the threads.