Some people have suggested the idea of attaching a dinghy astern of a race committee signal boat in order to give it some protection from racing sailboats running into the RC boat, especially over-aggressive barging racers. Another suggestion is adding to the pin-line bias, to try to get people away from the boat end of the line. There is a problem with the dinghy-drop idea, however, in that the dinghy would count as part of the RC boat, increasing the area that racers have to avoid while approaching the line. Assuming a windward start on starboard tack, this narrows the approach lanes to the line, effectively making the line shorter. This is perhaps best shown by a drawing an example picture.
In this example, the effective length of the starting line is reduced by 20%. With more congestion and crowded comes less freedom of maneuver, less reaction time, and more chance of collision. If you drop the dinghy further astern of the RC boat, the problem becomes even worse.
While it is true that the effect would be less on a longer starting line, too-long of a line also has its problems. A long line magnifies the effect of line bias, providing a bigger incentive for boats to crowd the favored end. That brings the poor race officer back to the original problem of increased congestion, potential for collisions, etc.