I believe yew cannot bend as far as osage and some whitewoods before failure. Failure in osage and whitewoods is more likely to show as set while yew will explode! The lever bow style has a short working limb which has to bend farther proportionally than a long full compass bow. For yew, cedar, juniper or other exploding wood I would want sinew backing on the working limb of a lever style. Also, for fighting armor you need very heavy mass arrows. In general long compass tiller bows push mass better while short limb bows make more speed from moderate weight arrows. My 2 cents...