Hate to raise the noise level a bit on the carb balancing mantra, but here:
I've used everything there is, from the Eyeball through a UniSyn through Harmonisation -n my decades of doing The Balancing Act. By Ear works, but you need to have a feel for it. UniSyn works, but is crude. Manometers work but are a kludge to set up. The Harmonizer is easy to use and deadly accurate but you need vacuum fittings on the carb or intake. I added vacuum ports to my R60's slide-valve carbs and use a Harmonizer in the shop and on the road.
But the shorting method is quick to use and reasonably accurate ( I would give it about 95%). The shorting adapters are easy to make (use an aluminum piece off of an NGK sparkplug and a couple of inches of M3 machine screw which "fits" better than a #6x32 screw).
Main thing is to UNDERSTAND what the principles are and what you are doing and just not going through the motions.
PS-- good post, Renner.