well i've found a post on another forum from T_T that contradicts what i say. there's no doubt T_T is a valuable and knowledgable member of the forums, but tbh most of the stuff i read smacks "alarmist" to me
put it this way - 99% of people who drive a DSG will not know it's any different to any other automatic. if VAG designed a gearbox that looks to the untrained eye like a torque-converter auto gearbox but needed driving differently or it'd wear it's clutch packs out they would have designed it badly and gearboxes would be failing left, right and centre and they aren't.
i don't for a second think that VAG engineers are that absent minded, so i'm happy leaving it in D when i come to a stop in traffic. if i'm stopping long enough to consider putting in it N i'd turn the car off anyway.
the only issue i have with this is that at night time you dazzle the driver behind you with your brake lights, but if you use the handbrake the car strains against it for a second before settling down and i don't like that either. (that is also proof to me that the car dips the clutch when stopping - because you can feel it doing it if you leave it in D and put the handbrake on.)
i'd never coast in N in any car lol.