Randy,
You're right about the recommended soak times being for steel 1" thick. But from what I understand it's still good to soak any piece of steel for at least a couple of minutes, just to be sure you have full solution. The spine on my blades is usually 1/4" thick, and I like to make sure it's evenly heated all the way through.
1086 and similar steels come into full solution pretty quickly. Steels like O1 need five to 10 minutes in blade cross sections. I think the soak time for O1 is 30 minutes per 1" of thickness, so you can extrapolate downward from that.
The soaking thing is assuming that you're able to control the temperature to the point where you aren't going to overheat the blade. If you have some control, soaking won't hurt anything except maybe cause a little extra decarb, which you'll grind off anyway.
If you can't control the temperatures fairly well, soaking is risky. Overheating is just about the worst thing you can do to a blade...
Josh