Swingtop said:
Then why are you not seeing him as a cobble rider? That's the first thing that came to my mind when he left the field. (yes, finally a successor for Knaven!

) And he has said multiple times that he wants to be good in the Flanders classics. Remember him going in the Tour of Belgium on the cobbles, dashing away, just for testing his legs?
But the worlds will be a nice example of how much body he has for 250k races, which traditionally favour older riders with muchos kilometros in the legs.
The most used and most faulty generalisation of all is that cyclo-cross riders are seen as possible good cobble riders.
While history, especially recent history, shows us again, again and AGAIN that they are not. In fact, they all seem to be very explosive and very good on hills.
Sven Nys tried for years to do well in Paris Roubaix, he was never succesfull.
Than he competed in the Tour of Belgium, and....he forced the selection on the Muur de Huy (this was a few years ago). And he is not the only one.
Albert wins a few hilly races and was the main animator together with Boom on the Tour of Belgium ardennes stage this year. Also saw some explosive attacks from Klaas Vantornout, another cyclo-cross rider.
Thijs Al, another cyclo-crosser, won some hilly race in Limburg, also by putting in attacks on the hills. He then did the same at the Dutch National Road Race, attacking a 800m hill with an acceleration and only Gesink following.
Cyclo-cross riders are generally good at interval, thus hills, and I've only seen them suck at cobbles.
And good thing you refer to Boom 'dashing away on cobbles'. Because if you really remembered and watched correctly, you saw Rick Flens flying over Boom like he wasn't even there, he had twice the speed of Boom. And Rick Flens isn't exactly a PR-winner.