Thanks for the input and encouragement, guys. I'm considering backing for two reasons, the first being a little extra insurance against imperfections, and the second for practice when I end up doing my Osage bow. I'm going to try rainbow trout skin over the silk this time (because I have a lot of it in my freezer at the moment) and on my Osage bow I'll be using brown trout skin or a combo of brown trout and pike skin - partly for the look, partly for the function, partly for the predator mojo. If you've ever caught a 'hangry' brown or pike, you know what I mean!