Plan B; with self bows you take what you can get. I prefer to reflex a deflexed stave over a form gently with heat. But, I often do find a stave that dries or grows with just too much reflex to handle normally, like 8" or something. So you can kink it back at the handle, or at the fades on each side, to get the total tip reflex to a manageable level. Either way. It helps to rough them down a bit first, of course, and it helps if the original deflex or reflex the stave had is even and symmetrical.
Bushboy is right, elm and some other white woods, and even osage and locust will tolerate a pretty big concentrated bend, even when thick, and really it only takes a few degrees. I have done all kinds of things just to learn about it. Like chopping and splicing at the handle, thinning and then building back up after bending, I even cut several saw kerfs to a consistent depth in the belly side of the handle, made the bend and then glued in shims.
I do think this works best in laminates, because Perry reflexing the right materials is like magic. But it's great with selfbows, too, and they shhot, esp since you have tempered the belly. I like that it is easier to bring the tips into alignment than it is with recurves, and that long gradual curves are much easier to convince the wood to settle into. I like that you can make a mildly R/D Molly and not have lateral tip issues much.
Technically, if you make a flatbow that takes a little set, heat treat the belly and flip the tips a bit, that is a R/D bow, but I think that engineering the deflex into the handle and getting that advantage is better.
