From our conversations with Ian et al, what Chess said has a lot to do with it. Historically, the technology simply hasn't been there to do it reliably.
With all due respect, I find that very hard to believe. Other companies do it, and we are talking about a very low frequency response. WiFi transmits at 2.4 GHz, and even with multiple sampling and error rejection, I find it very hard to believe that frequencies between 20 and 100 Hz cannot be transmitted reliably and wirelessly in the same room in the year 2010.