What I mean is that you have to already know how to dress well according to conventional style rules. I know that any one of TTO, Tirailleur, Butler, Barims and a few others here, could, for example pull off perfect CBD if they chose to. I am not sure that many of those who do perfect CBD or other more conventional SF-approved male style here could do what these four do as well. I think it is unusual to find a genuine peacock in the MC idiom who has just evolved their look(s) without first at least understanding, if not mastering, what makes conventional male style work. Peacocking (or for that matter, the particular extremes of the spectrum in dandyism or foppishness) requires a justified self-confidence.
FWIW, and no offence to Spoo here because he dresses far better then me, I think Spoo is actually only just getting to the full understanding and mastery level now. I don't think his previous more flashy style worked all that well, despite some nice components. However, if he was to give in to his peacock instincts again now or later, he would do it a whole lot better. Whether he would want to or not is another question - it would be entirely a matter of personal comfort and he seems pretty darn comfortable where he is (i.e. getting to the top of the game). Sometimes knowing that you could is more than enough.
As for most of what else has been posted so far - see Moo's old fits here for a prime example - I would class it merely as garish or bad taste, not peacock, or it is actually too boring and unadventurous.