Flat racing's Mr Nice Guy may still wear a smile on the outside, but underneath he has a steely determination.
Darley says: "I was probably guilty of being introverted and I'm not sure I express myself properly - that probably didn't help me in the past. I was a bit too quiet."
His winter trip to Singapore did not work out and he left after getting only a few rides, but his chances of retaining the title then received a boost.
Mark Johnston, numerically the strongest trainer in the north of England with a string of 180 horses, put Darley at the head of the stable's pecking order, along with Darryll Holland for the coming campaign.
Darley's agent Terry Norman has made up for his jockey's natural reticence in the past and galvanised him towards the title last term.
He revealed: "I call my kind of planning for Kevin 'the flea syndrome' where we get on the back of one trainer, and when it is time, hop on to another. However, a flea can run out of dogs to hop on to."
That does not look like being the case this season, though. Besides the backing of Johnston, Darley will also be used regularly by handlers Tim Easterby, Gerard Butler and Nick Littmoden, among many others.
Ironically, prior to his accident, Darley was race-fit for the coming season having ridden winners on the all-weather surface .
Darley and Fallon were due to cross swords, not at Doncaster, but at the World Cup meeting in Dubai this weekend when the former was due to ride Pipalong for Tim Easterby.
Despite his ground-breaking title triumph, prior to his injury, Darley was only 3-1 third favourite with bookmakers Coral for the championship this season, behind the odds-on Fallon and Quinn (3-1).
Betting on the title race has now been suspended but Darley does not regard himself as a longshot shot and says: "It's obviously going to be even harder with Kieren going all out for it.
"But, as I've said, I won't be doing anything differently. I will be chasing around because I survive on winners."