Frank. The only time you change a dual mass flywheel is if the garage is ripping you off, or it too is badly warn.To be badly warn in 65,000 means it has taken a lot of abuse from somewhere.
And as Alan says, the most common problem is that people keep slipping the clutch,for long periods of time,couple this to, in a diesel engines case the massive torque available from such low revs,just makes matters worse,and indeed not something you would have come across even with either a ford carpi 3.0 or a rover 3500. so today's clutch is superior to yester years,but the engines also have far greater low down torque.so Regardless of how many miles one has driven,it does not mean you are a master of the technique required for the new type of clutch release system.Which indecently is fitted to 50% of new cars.
quite simply if it starts to smoke you've already gone too far,and you need to let it cool down, or try a different approach.