Is this the link you mean?
50 Dollar Paint
I think if it works it is a bloody fantastic way of doing it.
I reckon also as it is a bit of an art using a polishing machine this is an ideal way of learning how to polish - if you cock it up just brush on some more and wait for it to dry.
I'd like to buy a cheap Honda myself to try this out on - well I would if her indoors wasn't likely to go ballistic 'cos there'd be two cars on the driveway in bits...
...if I were to do it to a Honda I'd even say oh bollocks to prep-work and just sand it smooth and degrease with something like this =>
http://www.autopaintsbrighton.co.uk/u-pol-system-20-panel-wipe--degreaser-fast--slow-5-litres-226-p.asp