I've done the Campy method of dry tapers and loctite on the bolt and a single torqueing. I've also done dry with no Loctite and retightening the bolt slightly several times after riding. Somewhat surprising, both methods have worked well. Seems I have faith in both methods, but not in one over the other.

If you haven't found a reliable method that keeps your cranks on, best carry a wrench. Murphy can rear his ugly head at any time, regardless of periods of reliability. On rides long enough to carry more than a simple tool kit, it would be good to have some means of snugging a crank bolt. I have a Sugino crank bolt socket with a rod for a sliding T handle that is a perfect portable tool. I've never taken it on long rides before, but I may consider it. Any ride that needs that level of repair capability also needs a chain tool and some spare links.
I commend the OP for finding a solution. It is amazing that something with the potential of coming apart even with a bolt in it can stay together without one.