Audi A3 Cab - better than an A4?

Spent last night getting acquainted with the new A3 Cabriolet. It's not the world's most masculine car, but it was surprisingly good to hustle around the countryside and motorways.  But it wasn't the decent balance and handling that really surprised me. Rather it was the fact that my bottom remained comfortably ensconced and free of bouncing and jarring on all but the worst of the rutted countryside tracks that make up much of my journey home.  Great – a cabriolet with admirable cabin insulation, good looks, room for four adults and engaging dynamics. So why, if Audi has managed to create a soft top that can maintain all these things without sacrificing suspension at the alter of 'sports handling', can they not do the same with the new A4 saloon?