I have not tried to reproduce this finish yet, but, like Brunswick, your approach, while as valid as anything else, seems the long way around, with many possible misteps along the way.
I'm a strong believer in keeping procedures as simple and straightforward as possible, when and if possible. This is why I prefer to use a polish that has the least abrasive grit in it as possible, like Valentino's Snake Oil, as just one example. I'd suggest starting with a sanded surface and then applying such a polish.
Of course, sanding is also approachable from 2 points of view. A, a step wise approach, such as 500 grit, 1000 grit, 2000 grit, then 4000 grit, or, B, a sudden change, such as 500 grit, then 4000 grit. Then applying the polish.
Alternatives will let you do the same with a 2000 grit or a 3000 grit starting surface.
As for polish, you can put a light dose, medium or heavy dose of polish.
Sanding with specific grits seems a more specific way to get to a starting point rather than using a strong abrasive compound such as Rough Buff or Storm's Step 2, which involve a lot more variables in their application onto a bowling ball surface.
Just another point of view in the pursuit of KISS ("Keep It Simple, _____"). The simpler it is, the easier it is to repeat.