Firstly, let me say how pleased I am that there are some Western Crews coming out the Nationals next weekend. It's no small time and financial commitment to do so. All indications are for a great weekend of racing.
As for lanes etc, I wouldn't spend too much time worrying about it. The course is being rigged for Canoe racing with what I believe will be only 4 relatively centrally located lanes with ghost lanes in between.
With the conventional 6 lane setup for Dragon Boating they use for the Montreal IDBRF cross winds, depending on direction can help/hinder lanes one or six. Hopefully this will be less of an issue given the 4 lane setup. I am sure they are very sensitive to making it as fair as possible.
On top of that, since there will be a Preliminary and a Semi before the Final, all teams really have two chances to position themselves favorably/make the final. If there is any lane bias due to winds etc, then a team that gets a less favorable lane in the preliminary will still have a chance to recover from that in the Semi. If a team cannot make the top 8 from any given lane then it's a tough sell that they would be top 5 in any case.
On the other hand, if a team were to get a favorable lane in the preliminary, then they would still need to back that up with a top 2 finish head to head in the Semi to make the final.
Best of luck next weekend and don't be strangers. When do you fly back? Some of us are staying over Sunday night to... ummm... go sight seeing or something
