Cheers. It's an interesting one as many of the Yammy BB owners on the mega-thread also swear by the P+J in combination.
I guess the other way of thinking about fretmeister's point, that I have heard expressed very neatly, is that whenever you blend the neck and bridge pups it can lead to a mid-scoop, which can sound great solo'd but will likely cut through less in a band mix. However, I've not particularly noticed that with my blended Yamaha PJ settings, but that's maybe because they have such kick-ass bridge Js!! (Well certainly the BB 424/5 and BB 1024/5s).