I don't like your comparison...a bit extreme IMO. As you said, the World Cup is comprised of the best players, period. The best players of WOHD, not Pure or Pulse, which is where these new tracks came from. But the best WOHD players out there don't all know the new WOHD tracks from Pure or Pulse yet, as they are NEW (to WOHD), hence a potentially unfair advantage (IMO) this early on. If the WOrld Cup weren't for 6 months from now, then no problem, but that's not the case. OBH already offered one reason why incorporating the new tracks might not be a good idea and I was simply offering another.
@ Leungbok - I hear what you're saying, yes, the handling/feel might be different in WOHD, but the most critical aspect of "learning" the tracks is memorizing their layout, of which will take longer for those of us who have never seen these tracks before.