Ok, so I have been able to personally be a part of the ODP process from both a player and now a coach.
As a player, definately worth it! I left the program at U16 due to my knowledge of the players I was competing with in my position for Nat'l team (Susan Bush). As for how I was selected... I was a player on a small independent club team that was premier level. My coaches, who were not in the ODP system as coaches nominated me! I then had to be aware of the fact that I would be scouted at any game (as it is random and you won't know when the coach will be there). I must have done well, I got invited to tryouts. Once you are in the system it is easier to stay in, but not a guarantee.
As a coach, politics are in any system, whether it be sports or business at work..... we all know this.... don't play dumb! Does it help to have your coach in the ODP program, I am sure it does, if THE COACH, knows the head coach of the age group your child is in. What will the benefit be?? A simple closer look maybe...... I don't know. I was only an asst. for a few practices this year due to schedule conflicts, but this never happened at the age I was with.
It is the coaches responsibility to do the RESEARCH of the age group they are coaching in. Know the teams, know the players, and then if you have a player who is of "ODP caliber" nominate them so they can be evaluated in a game like setting. Some coaches ruin their credibility by nominating everyone and it wastes the time of the ODP scouts who in turn cannot see every player. (Possibly why some players squeeze through the cracks.... lack of coach credibility, or lack of time)....
This is my personal perspective..... how I see it..... other views are probably different!!