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You are correct. The American National and Unified Screw Thread Form has .125 x pitch for the top of the thread and .250 x pitch for the valley. This will increase the strength of the bolt slightly but unless the bolt is being pushed to its maximum strength limit it is another issue to worry about when grinding the tool. This is expecially true eyeballing it with a bench grinder. I have a single lip cutter grinder and can accurately grind a threading tool with a .250 x pitch perpendicular to the cutter with the proper clearance angle. In practice for almost all general applications, especially grinding the tool by hand, I have found that a pointed tool works fine.