Don't believe it for a second. A practical, inexpensive, commercially available and simple denitrator is the only thing that could ideally reduce the amount of water changes necessary. In Saltwater there has been significant advances using elemental sulfur and denitrifying bacteria which feed off sulfides, but this has yet to be attempted in FW as far as I know. This utilization of sulfur-reducing bacteria gets around the age old problem that the bacteria which break down nitrates typically only exist under anaerobic conditions.