Yawn. We get this argument every year and I confidently predict yours won't be the only thread started on the subject. I'm already working on my dissertation about why being a DIRTY RINGAH! is no advantage on this show but, frankly, you could write it on the back of a matchbox:
'The winner is the celeb whose journey people most admire.'
There has been, IMO, only one exception to this rule. The ringiest ringer of them all to win is probably Jill Halfpenny, but she denied she had any dance training and maybe people believed her (fnar, fnar).
My two favourite winners also had some dance training (Alesha Dixon in series 5 and Kara Tointon in series 8) but they both had amazing relationships with their professional partners and that probably had more to do with their winning than their technical competence.
The rest of them? Natasha Kaplinsky, Darren Gough, Mark Ramprakash, Tom Chambers, Chris Hollins, Harry Judd, Louis Smith and Abby Clancy - every single one of them a 'journey' contestant.