Steve, you're correct. It's virtually iimpossible to out perform the stock ECM when in comes to it's ability to maintain stoiceometric air fuel ratio, but it's not so good at full power fuel control.
I've found the best of both worlds by keeping the stock ECM in full time closed loop. (In case no one has watched it happen on powerlogger, the stock ECM drops out of closed loop at just about 0 minifold pressure) Therefore the idle and cruise is controlled by the stock O2 which is perfect for stoic. air/fuel control.
But when going to wot my wideband O2 takes over and maintains the air fuel ratio that I have commanded it to do, via my Translator Pro. It's a great sinergistic(sic) relationship between the two.