Nah, I'm on
@thestelster 's page.
Of course, you are right about how the single point tool gets distorted as you tilt it. But for a grinder you just form the grinder profile as it is when it's grinding.
In my mind I see it a wee bit like differential equations. As you tilt the grinding wheel and correct the profile, tilt the wheel correct the profile, etc and take the limit of the corrections needed till you get to infinity, the grind stone doesn't know its tilted to the helix angle. It just cuts the tilted profile into the thread.
Said another way, the profile in the direction of rotation of the grinding wheel isn't the same as the profile on the plane 90 degrees to the shaft axis. But if you take a section of the wheel at 90 degrees to the shaft axis, it is the same!