The brushing is exactly what is done with the machines at slow speed. I am sure your job is more precise since you could count the brush strokes.
I am not so sure about the ink. It looks nice, but would worry about the long term wear. Over time, when it dries, it might crack or fade unevenly especially if the surface was not treated before.
If it works, I am sure you can rival Breitling's service at 1/60th the time and proobably 1/200 the price!