When Sky was first created and they said "a British GT winner in 5 years", and most scoffed (including myself), the question was, where was a GT winner going to come from? Wiggins was, at that time, a one-hit wonder who had got away with burying himself in a very conservatively-raced pack and benefited from an incredibly easy parcours with a long TTT and neutered mountains; as soon as a genuine mountain stage came along and the likes of the Schlecks had real reason to fear him, he was dropped and they put three minutes into him. There was little reason to believe that he would win a GT until he'd shown it was not a fluke born of favourable circumstances and/or parcours (see also: de Gendt, Thomas; Arroyo, David; Cioni, Dario; Velits, Peter for various examples of one hit wonders in different forms).
Froome was barely mentioned by anybody, which is strange as in 2009 he hadn't actually been too bad (as opposed to a year later where if somebody said he would win the TdF one day you'd have been laughed out of the room) although his most memorable moment was the Taaram?e on San Luca (this being before Taaram?e did his own legendary Taaram?e, which was on Xorret del Cat? in the 2009 Vuelta).
Kennaugh was the name people mentioned. He was the one British talent who had shown something on climbs. He hadn't been a monster talent like Jamie Burrow was (as blackcat mentions, Jamie Burrow is probably the most talented British climber since Robert Millar, I say probably because an argument could be made for Emma Pooley), or anything, but he had at least shown he had a talent for climbing that, if nurtured, could take him somewhere. But then, look at the competition in that Girobio. Cayetano Sarmiento won the race, and hasn't turned out to be on the same level as the other Colombians who came through at a similar time, unfortunately. There's still time for him - after all, Winner Anacona's breakthrough came in the second half of last season after a couple of barren years - but he's not exactly set the world on fire. Manuele Caddeo, who was second, went on to a year of achieving bupkiss on Colnago-CSF before disappearing back to amateurs. Kristjan Koren and Cesare Benedetti, 5th and 6th, have carved out decent niches for themselves at a good level, but neither are climbers that say Kennaugh beating them is a huge surprise. The strongest opposition in that field based on how they've turned out as pros are actually some way down - Richie Porte, Winner Anacona, Dominik Nerz.
Kennaugh turning into a strong climber isn't a surprise. In fact, given all the transformations going on at Team Sky in 2011 and 2012, it's actually more surprising to me that the guy who was supposed to be Britain's GT winner when all of those transformers had yet to do so, has taken until now to make that progress. Some teams like to bring riders forward very young (Liquigas, for example), while others tend to molly-coddle promising youngsters for two or three years (Caisse/Movistar, for example). But I really thought that given how he'd thrown a bunch of other young riders to the wolves, Brailsford was being over cautious with Kennaugh.
As things stand, the most suspicious thing about him is that he rides for Team Sky and he says a few things that seem too blatantly to have been prepared for him by the PR team which make him look like a disingenuous tool.
Lets not overrate pre Sky Kennaugh. He was a decent young rider and way better than jokes like Wiggins and Froome at that age, but he was still not the top rider from his age group and certainly not likely to become a gt contender.
GT winner? Never in a million years would those 2 words be put together as a potential achievement for a rider with those results in any other country.