Have to remember that age plays a huge factor in roster selection. You have to be incredibly skilled to keep up with players two years older than you at that level. A ton of development happens at those ages and mediocre 19yos are often better current players than any high-end draft eligibles.
It's one of the reasons that Junior clubs tend to like their overagers, because they won't jump ship to the NHL but are at the top end of the player spectrum in juniors. I think that's another reason a lot of WJC performances incorrectly inflate value. IMO it's pretty easy (and I'm guilty of this too) to lump all WJC players into one general age-bracket, when really there's an enormous difference between a 17yo and a 19yo.
