I have 3 boys playing travel (Goalie, Defense and Middy) and have been involved with about 6 teams over about 18 combined seasons and I have always found the "D" coaching to be excellent and so much better then they ever get in the school teams until varsity for teaching defense. unfortunately you might be on a team that is not well coached, private lessons for goalie and offense is great but it is very hard to learn defense from private lessons because it is such a team concept, they can learn one-on-one and footwork but good defense is learned from team D. Find a better situation for your D-man