yes, if we also want to have a bow with constant fiber stress, then limb bend shape is dictated by thickness. There are also places along the limb where we might want to have less than max strain. I am thinking of many designs where it is desired to keep the center and/or the tips bending slightly less, especially during the tillering process. These stiffer areas can be said to have less strain. Are you looking to build something like the ELB presented above? I recall you working exclusively with constant thickness pyramids in the past? The design I posted above,(tips @ 1/2 the thickness at the center of the bow) allows for a mid handle strain that is 90% of the max strain at midlimb. I by no means claim to know much about ELB design or tillering, and suggest the taper as a starting point for development. Perhaps some of the bowyers from across the pond would be willing to offer descriptions of tapers used in established designs. If I remember correctly, I have seen designs that start the width taper closer to the handle area, and so may not have a straightline taper in thickness, but perhaps reduce the rate of taper out towards the tips.