I've been to a few "large Florida races" with the new starting system (I presume you refer to the shortened sequence?). It's been good for the most part, and the only issues I've seen is when the RC forgets to put the correct fleet flag up or changes the order of the fleet starts and forgets to tell us.
Usually there are at least two starts (high and low portsmith), and more if there are enough of one type to have a fleet. Even if you don't quite get the idea the first time, you can tell when all of your fleet-buddys are creeping up on the line that you should be doing something...
At Tradewinds, all fleets shared the same finish line, and it wasn't a problem. The two courses (shorter one inside longer one) only posed a problem when the big guys were screaming to C mark, and the little guys were a bit in the overlap. The line was big enough for all, and a barging bouy was floated behind the RC boat after we backed into them between races.
Another big race (Miami Key Largo) split the line with the RC in the middle. monohulls on one side, multis on another. Theoretically, this could allow two fleets to start at the same time if it were all multis, but there would definitely be a little squabble over which fleet gets the favored side RC boat.
The shorter start sequence also allowed more races per day, which helps out teams like us, who try to wear down the good guys...