My 2 cents .If a lake is chucked full of shad and small crappie , Make a half and half limit 10 small fish and 10 over 10 inches. If Crappie life is 5 years taking the smaller fish should help the larger fish grow at a faster rate. also a larger crappie will eat and be able to eat larger shad. I am mostly a walleye fisher I know this will not work for most novice crappie fishermen. What works for walleye in the mainly walleye northern lakes. is keep the 13 to 15 inch a few up to 20 and one over 20. Leave the spawners in the lake for the most part. I don't see what it would hurt to let fishermen keep a few small fish along with a few larger fish. In the long run it should increase the numbers of larger fish. and that is what most of us are looking for . And you wont see all those smaller fish floating on top of the water. I don't think all lakes should be lumped into the same regulations for each lake. get more creative on length and creel limits. Like they say you don't know until you try.