I have a problem in producing a dough that will "stand up" . I use a 70% hydration and a 1-2-3 proportion for starter, water and flour. Whether I knead it a lot or a little I cannot get the "satiny" description used in most baking books. Mostly I use a rye starter and a mix of French flour and strong white. It rises well in a proving basket, but flops when I turn it out and slash it. Baking at 250 with or without steaming I get no oven spring.. Where am I going wrong?