Well my dads A4 was just under 3 years old, so still in warranty, thats the reason Audi ended up cashing in. It's never been used to tow, and only has two people in maximum for most journeys, so it's hardly stressed.
To make matters worse, my uncle in his a4 had the same problem at 44k, again be raped by Audi as it was under warranty, with them refusing to budge on fixing it.
Then last week, his best mate had his dual mass clutch go, with the total sum of 4k miles on the clock.... hence why my cousin wants to get rid of his aha
Clutches should last more than 40k, and my dads flywheel, in warranty, had 'damage' caused from the clutch - if we werent so stressed at the time, we wouldnt have accepted it :/
Your old man had some bad luck there, i've had 4 VW's (TDI's) with the same engine in two and between them all i have racked up over 170,000 miles with no issues with regards to the DMF's Yes they are bloody expensive and my mate who used to service my car recommended going over to a standard flywheel clutch combo.