This is something I can definitely see a use for. My layout is DCC and in the loft but i've been looking at making some small shunting layouts I can play with in winter when the loft is too cold. This solution removes the need to buy another dcc controller setup whist retaining compatability.
There is huge potenital here but Hornby don't have a great track record with dcc so hopefully they've brought in some new people who actually know what there doing.
The other thing i'd like to know is the compatability of these chips with coreless motors. I had problems getting a next18 chip to work with my Bachmann 94xx as many, particularly budget, decoders dont work with coreless motors.