Black is the worst color to work with when it comes to detailing. I imagine the Miguaires (sp.) 3 step process is simular to what I would do back in my younger days when I was a detailer for variuos auto body shops. To get oxidation (junk) off and get down to the finish I would use what we called "rubbing compound" or "buffing compound". This is basicly miro-fine liquid sand paper which is good for slowly removing oxidation w/o removing finish. There are varieing grits, you'll want the fine grit.

Once the oxidation is removed, you want to apply a good protective wax - the brand is up to you. This will provide a layer of protection between your car's paint surface and the environment. You can throw on a few coats if you'd like. Afterward, you'll want to buff the wax with a polishing compound until your happy w/the results. Finish off with a mirror glaze product. It's a temporary glaze that nicely fills the fine scratches you see as swirl marks. You'll want to reapply the glaze after every wash.

I always found that using a maching to buff always ended up with swirl marks. I could get away with it on a white car, but any darker colored cars (esp black) I had to use the good ol' fashon method of hand rubbing the car.

To try and remove swirl marks I'd acutally use the same process as above, you may be able to skip the rubbing compound step, and try and fill the swirl marks w/wax and then polish the wax and finish w/the mirror glaze.

Rubbing compound - physically removes surface mircoscopically
Wax - acts as a barrier to protect the paint finish from the elements
Polish - polishes the wax, ideally to a near mirror finish
Glaze - acts as a temporary filler, to fill in any mirco fine scratches (such as swirl marks).