Acoustic Guitar Construction

The bridge, bridge plate are combined into a (the) major structural brace on the sound-board -- the best glue joint in my opinion can be achieved if these components are as flat as possible. I personally can see no value in doing it any other way -- appearance, structure, sound quality. -- But hey what do I know?

My sense is that it does not really matter. As a brace it is not really tall, even if building with a radius it will quite happily bend and conform with the top to the bridge when the bridge is glued on. I view it as targeted sound board reinforcement. I have put the bridge pad on first to act as a guide for the Xbraces, in that case I just glue it on flat. I have also added the bridge patch after the xbraces, then, as I use radiued braces, I glue it down in the dish. I have never sanded a radius into the bridge plate.