With respect to the "B" fleet thoughts, I wouldn't want to sail B fleet, even if I was new. I'd rather take my licks and know where I stood in the overall picture so I could find someone at a higher level and learn from them how to get better.
Perhaps a "B" fleet is necessary in a high-stakes regatta with lots of boats, where me as a newbie could really screw things up. Like if I flipped over at the starting line in front of everyone (because I was over early). Or if I dragged a mark just before the rock stars lapped me on a course 7.
Then again, maybe that's just something the rock-stars should have to deal with... loose cannons like me adding another layer of tactical challenges to overcome. That's why they're rock-stars, right?