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In the olden days, you could preload a headset by feel. Too much and the bearings felt crunchy. 1/4 turn less and the front end would be all wobbly. 1/8th of a turn back the other way and you'd find a balance of sorts.
Nowadays, my (integrated) headsets in my nice bikes seem waaaay better. It's almost impossible to over-tighten them to the point they feel notchy. Presumably this is because they're bigger bearings with better tolerances or something.
The point is: Given that there appears to be a wide window of perfectly 'acceptable' headset preload, how much should you dial up? Do you use the bare minimum necessary to remove wobbles? Bare minimum plus a bit in case something slips? Or do you crank it down hard to avoid any bearing movement within the race? My gut feeling is bare minimum but is there an accepted practice? WWSTWD?
I probably still limited myself to "just enough" as I learned with 1" headsets on threaded steerers.
However, angular contact bearings, which headsets are, will be tolerant of more preload than the deep groove bearings found in other parts of the bike.
Same way I've always done it - hand under stem on top cover, nip up until there's no more play, done. My bearings seem to die from water ingress, not wear though!
I go with submarined method above.
I don’t have to replace bearings often, and when I do it’s water ingress.