I think once you are in this hobby for a while you will see that all the current methods are opinions and that each one has its own facts to be presented....in the end it is a lot similar to politics.
I won't turn this into a debate, but some things to consider with a deep sand bed that the smells are definable. Sulfur is a normal byproduct, any strong "sewer" smell is probably that of a improperly maintained substrate, while a slight smell (when the tank is empty and you dig through the substrate) would be likely to occur since this completely different approach to BB actually uses these nutrients to feed the macro/micro populations at work.
the fact that bb and forcing LR to release its nutrents has been a method for keeping more difficult coarls in aquaculture/reaserch when the hobbiest couldnt keep them says something to me as well..
And substrates and deep substrates have been used in the commercial and aquaculture industries for decades. Then it is also important to not overlook the use of turf scrubbers, ozone, etc. in commercial and public aquariums for many, many years.
What it all tells me is that all applications most likely have there place in the hobby. I would suggest Ultimate Marine Aquariums
by Paletta, it shows a great history of some of the most successful tanks and the wide variety of approaches/equipment used.