I don't know about a balcktail, but on the bows I've made, I just put the two different woods on the back of the bow. That side is seen more than the belly. That's the reason I did mine that way. As far as weakness, the spliced woods are a thin veneer and add mostly looks. The cores under them and the glass over them do most of the work. Shouldn't have a problem with a weak spot. Mike