I was just in another thread :
http://www.dakkadakka.com/dakkaforum/posts/list/538053.page
Half way down page 1 he creates an almost similar effect with symbols on the armour, fading and such. Take a look.
What he says he does, is that he actually creates the colour gradient first; the reds -> bright reds and fading as such, then he paints the black on. So in effect working in negative. That could easily be applied to the model above.
Simply buy painting the bright red on and then fading that out with darker red perhaps some washes and then finishing up with the black outlines, you'd have an effect very similar.. Its a simpler technique than the reverse and is infact widely used in many other applications. But the obvious statement to make is simply: its patience vs feeling finished. The model your showing probably took a considerable amount of time; which there is often no way around
But i myself am gona try this negative method. Seems really interesting