Let's be real for a minute. No single tool maker (re)profiles and sharpens a cutting tool at the same time. First you need to establish the proper profile. Next you need to put an even bevel on that profile. Then you hone that bevel till it suits your needs. Whether I am talking about a woodworking gouge, a billhook, or a smiling razor makes not the least bit of difference.

By far, the easiest way to grind a smiling curve on a razor blade, is to put it with its edge down on a coarse hone (the DMT 325 is great for that), and "breadknife" with a rocking motion. It's easy to control, and pretty quick too. After you made the curve you wanted, you need to put 3 or 4 layers of tape on the spine and start using the rolling X-stroke. Use the same coarse hone and apply a bit of pressure, while completing the bevel till it extents all the way to the apex again. Next start backing of on the pressure, reduce the tape to 2 layers, and move up one grit-level. After that, finalize the bevel (with or without one layer of tape, according to your personal preference) on your normal bevel-correction hone (such as a DMT1200).

That's it.
Hone as smiling razor after that.

All the rest is making a straightforward task very complicated.

Bart.