Whoa, Whao, DSB being bad? - that's not even close to being true - if done right, the DSB is beneficial to the system and should not leech bad nutirents into the system - again, if done right.
This months edition of Aquarium Fish Magazine has an article the shows that some people (namely me) are using a combination of the Jaubert, DSB and Berlin systems. I think this is on of the best ways to have your system running (knowing full well that every reefer has their preference - the DSB is obvious, the Jaubert System is a plenum covered with crushed coral and the Berlin system is a oversized skimmer and intense lighting). If I were to do it differently, I would include the little hose in the plenum to remove the water once in awhile - this is also, something the Jaubert system users have been doing recently to have it last longer without having to change the bed.
Additionally, there are many many people who have DSB's running for years (not 2 or 3).
Bottom line, there doesn't seem to be one scientific (empirically proven) way to set-up your reef. If you have a thriving environment, don't question it - and let it be - sit back and enjoy.
My .02
Jim