I built such a bow a couple of years ago and it worked great. I flattened and tapered the bamboo as you would for any backing, thinning with a block plane or belt sander to 1/16 inch or less at the edges. I tapered the osage slat to 3/8 inch thick (top to bottom) from 5/8 or more at the handle, so a more severe taper than might be needed for a mild r/d. I only used heat to bend the osage before glueing up the bamboo on the slat (this was a r/d with a near static recurved tips the last 6-7 inches). And I only used heat on the recurved tips, nowhere else. Then I buttered up the bamboo and osage with Urac 185 and clamped the bamboo to the osage on the form, just using c-clamps, but a clamp every inch or so.