One of the things I have noticed in my 28 years of racing is that spin trimmers are prone to over -trimming. Fast boats are constantly easing the sheet until there is a slight break in the shoulder of the chute and then trimming in slightly until it disappears. Slow boats have the foot of their chute down on the forestay. Another thing I have seen is that the fast boats have a crew boss who moves the crew[ballast] individually to maintain boat trim. The crew boss is usually not the helmsman, he should be focussed on driving the boat. The c.b. is usually not the main trimmer, as he is busy calling lifts and headers.[oh yeah, and trimming the main] The c.b. is a good job for the pit crew , whose job is halyards, runningbackstays, checkstays,etc... He needs to be contantly focussed on the deck instead of the fleet to facilitate the setting and dousing sails efficiently thereby making him the logical choice. Regardless of who you choose , it is important that one person control crew movement or on every puff there will be a race to the windward rail by everyone followed by everyone overcompensating by moving back to leeward. The boat will be continually rolling on it's beam ends and killing speed. While some sport boats do better moving crew aft to climb over their bow wake to initiate a surf, old IOR and your average PHRF boats only increase their wetted surface area doing so which adds drag. Putting the bottom of the transom will only create a speed robbing eddy behind the boat.I've found it best to have regular practice days with my crew. Experiment with boat trim to find the sweet spot on different points of sail at different wind velocities. Move crew to different jobs so they can appreciate what others are doing on racedays. In light air, I've even put the "dogs in the house".[crew down below on the leeward side as close to the hull as possible.]This helps to control the pendulum motion as the hull meets the waves. I would work on being the other P.Flyer's shadow for a while. One of the best ways to learn is to mimic others. as you learn what works well for them , you can begin to sail your own race, but that's hard to do from way back in the fleet.