Tell VW to shove their diagnostics up their arse and that your going to take it to a garage that knows what they are doing and knows what customer service is to find the fault, tell them if it is clutch you'll gladly leave them alone and pay someone else to replace the clutch, but if it's the mecatronics they have to fix it as it's a known fault and you reported it at 600 miles and if they don't you'll go to the papers and tell them how your nice new VW hesitates when pulling out of junctions and is not safe, especially as you frequently have small children in the car and it just stops half way out of a junction and that you have had a few near misses with kids in the car and how big bad VW just want to get out of fixing it and don't care for customer safety.
That's what a friend did with vauxhall when she bought a secondhand 02 plate astra that would just cut out all the time, it went back to vauxhall 12 times under waranty, they kept saying nothing wrong with it, she told them that she'd do this, she now has an 06 meriva for her troubles.
