Simple truth: People who lead runs have their wins. LS's that can kill the shark probably are full and dont need to shout. To get what you want you might have to step out and try a run yourself. No harm in trying, just take advice from experienced members and do the best you can.
I mean, I have gone on plenty of shark and bee runs, just never got the win. Got then down to 8 and 10% but never completely. I go with some random shout groups and also 3 that I'm in. But thanks for the responses. ^