Not surprised at all that the nosewheel came to a rest so far off the pavement. The -600 needs a lot of angular momentum at the start of the turn as it loses energy very quickly due to the pivoting stresses on the main landing gear. Particularly the inboard and center gear. Remember they are double bogeys and the mainwheels are turning very slowly while the nosewheel is arcing around at a fair rate. If you don't start the turn with sufficient momentum and thrust the aircraft will stop midturn, requiring a large application of asymetric thrust to get her going again.
In this case the angular momentum looked fine - but the judgement of when to start the turn was obviously off. With the nosewheel 5 meters behind the pilots position and the mains 38 meters behind, the -600 can be a real bitch to taxi around tight corners. Very easy to misjudge particularly if you are new on type. Having to do 150 degree turns is also very rare.
Everyone makes mistakes - but unlike most other profesions, our shortcomings are very visible and very public.
Hard luck guys.
