I think all you experienced racers underestimate how daunting it is for a first timer to be out on the water with multiple other boats, multiple classes maybe. Not used to being so close to so many boats, trying to figure out where to look for all the signals (let alone interpet them!), stay out of everyone's way, find the start line in the right class, find the marks and just get the boat around the course. Everyone says it's all just for fun but the race faces go on close to the start and it's not so fun for some people any more! I think if you're really serious about attracting new blood and being newbie friendly you could organise an introductory race, limited to newbies, where the experienced guys crew for the newbies and give them a few pointers. That would also help the newbs to see that you are just regular people too who happen to have been doing this for longer.