I agree with D-T on all this.
I think Boom is clearly in form at the moment. He's trained very hard for this. So said Paul Herijgers and don't forget he definitely wants to become Dutch Champion again. So he doesn't only have long term objectives. Last season, he won it in a tight sprint with De Knegt. He had only raced one cross before. This time he wants to make sure he's fit for it.
I have other examples in mind of crossers vs roadies rivalries.
I read a book about Roland Liboton in which he talked about his 10 winning streak at the Belgian championship and he said that on that race, roadies such as Eric Vanderaerden came to bother them. "We were tired and they were fresh." That's why Liboton is so proud of his streak.
And remember Igorre 2007. Mourey was dominating the field, a dozen of seconds ahead. He would have won if it wasn't for mechanical problems. Herijgers also said that top Belgian riders had been mixing it up since September with the best while Mourey was tranquilly winning his Challenge national races (by the way what was he doing again in Switzerland instead of Zolder?).
So yeah fatigue certainly plays a role.
Don't ignore other elements either. Zolder was on snow and ice. A very dangerous route. Willingness to take risks played a role too. Albert has never been a snow rider (don't know about Boom?). Pauwels has a snow phobia. Nys seemed to have back problems and in any case he announced clearly that the Superprestige was more important. And then Albert explained that he was losing grounds on the straight parts which favoured Boom clearly.
Also agree with D-T on Stybar's and Albert's road abilities. Even Pauwels !
Only problem is that their teams are not invited. Just look at Mourey. He can ride Pro Tour races because his team programme allows him to but he's never had good results on the road, neither with the pro nor with the U23.
Albert was winning something like 8 of the 10 road races he raced as U23 or junior each season. Stybar could be top10 in the Giro delle Regioni. Let's see what he will do with QS.
And Boom's comment seems ridiculous. Riding GT doesn't help for preparing the cyclocross season. Ask Franzoi, Mourey or Liboton. They all had bad experience with cyclocross season after riding a GT. Mourey said he lost tonus and gained stamina. Actually he was dieselized. Riding GT is certainly a good experience for a road career but not cross.