An extrememly successful chicken breeder my husband knows cranks his Dickey incubator up to 90% humidity for hatching. He also helps out every chick that has pipped by day 22 but hasn't zpped. He pops the tops off the shells then puts them back to finish coming out when they are ready. He hatches 500+ of his main breeds and many hundreds of others every year. He regularly sweeps awards in shows and has for decades with his own breedings. Does anyone else use that high of humidity?