There will never be a consensus to your question. For everyone who leaves no play and 30 years later the hubs are perfect, there will be someone who leaves a slight amount and 30 years later the hubs are perfect.
It is ironic that no one has ever developed a tool to measure pre-load on cup/cone adjustments. I’m of the opinion that good quality hubs operate at low enough ranges of stress and heat that it is probably moot as long as it is not too tight or too loose.
My personal preference is to adjust so there is a skosh amount that disappears, or not perceivable, when the skewer is tighten. It also makes the most sense to me. It has prevented the bike from swerving to far to the right or to the left.
John
Last edited by 70sSanO; 03-21-22 at 10:00 AM.