Mark, as Chad(nicholc2)pointed out, the manual setting section of your Pioneer manual mentions a "Plus" setting for the subwoofer which results in main channel bass going to both mains set "large" and the sub. You'll note that they don't emphasize this and the comments on its use don't really urge it. Using your term, yes this is in my view "counter-productive" to some extent. The idea of bass management is to relieve the speakers of the lowest bass and allow a good sub(especially one as good as your EP500)to do what it does best without conflicts with another speaker. Although the combined setting is sometimes said to give a "fuller" sound, that isn't necessarily better.
