I love a good zombie thread.
The Cronometro Nob is good for small, narrow lights or offset mounts, but a heavier light will cause you no end of grief.
Lights on the helmet are good for "smacking" drivers. But a really bright helmet light will wash out relief causing a loss of depth perception. To see what I am talking about, strap a bright flashlight to your fork, saddle up, and look down your driveway. Take note of what you can see: gravel, grass, twinkly bits (silica, both glass and sand), et al. Then put the light on your helmet. No need to saddle up. All of that relief is now gone.
I have been getting into using the Paul Gino Mount
lately. Much easier to install than a Besso and the larger diameter makes it easier to mount a variety of lights; no shims necessary.