@GoddersUK: Ironically(?) you could make the argument that using the phone as a controller, you'd still want a low latency architecture. I guess the question then would be, why should the low latency architecture be limited to just use as a controller and not also for sound related things.
Bottom line, I think it's more sensible to start with a low latency architecture and then tweak it at runtime for power saving or whatever needs, than trying to "sprinkle in" the low latency. It's a bit like trying to "sprinkle magic security dust" onto some legacy system (eg. C-based OS for home routers that won't get updated). Was there an alternative? Well if there was a home router running eg. Singularity OS from MS I'd have bought it long ago. I don't get it why MS didn't jump at such obvious opportunity to easily take over the market. (The only thing preventing me from doing it was that Singularity was not to be used for such purpose - but that wouldn't have prevented MS from doing so)