I use the time recommendation for my soak time in the forge, after bringing it to critical and letting it come back down to black at least once to relieve stress in the steel from forging & grinding. Most of the time I will simply soak at critical for 8-10 minutes and quench for O-1 or 1095. I believe most of us will temper for one hour at a set temperature, I double temper at 350F personally. I could be wrong, but all of my customers have been very pleased. Keep in mind that mind that I mostly sell knives, but have a handful of razors in our SRP member hands.