Turn and bank indicator during taxi

This feature is realistic. I am a pilot myself and it is even stated in the Pooley's checklist to make sure the DI (Directional Indicator) and the Turn Coordinator move when rudder is applied when taxying. You can see this in pretty much any youtube video of any aeroplane that uses a turn coordinator (unless the instrument's gyro or other parts are stuck!) - take this one as an example. As far as I can tell from the wikipedia page, the reason behind this is that the gyro that operates the instrument simply detects yawing motion, and the yawing force exerted when turning on the ground triggers the same response as it would in the air. 

Regards,

Max